Bench Talk

Engineering Electronics That Survive Orbit

Thu, 11 Jun 2026 03:34:44 GMT

(Source: dimazel/stock.adobe.com)

Picture a particle smaller than an atom hurtling towards a seven-figure satellite. The encounter is profoundly lopsided. The particle punches through the spacecraft, sometimes disabling systems or destroying the satellite outright.

Welcome to the weird and wonderful world of what space does to electronics. A single iron nucleus flung across the galaxy by a supernova can destroy very expensive equipment in milliseconds. And in space, no one can hear you—or your satellite—scream.

This blog describes how a single subatomic event in space can end a mission, and explores how surviving orbit demands electronics engineered for exposure, unpredictability, and time.

Understanding the Rigors of Space

In most rugged environments on earth, electronics also degrade over time. Cold, heat, sand, and water all take their toll, which is why the ruggedized electronics industry creates a variety of products for markets such as military and scientific observation.

Space is its own category of rugged. However, this designation is not just due to temperature extremes or even the slow cumulative damage from radiation that builds up over months and years, gradually shifting transistor thresholds until circuits drift out of spec. Space is particularly punishing because of single high-energy particles—protons hurled out by the sun, iron nuclei from distant supernovas— that punch through spacecraft shielding and dump their charge onto transistors.

These dangers are not limited to space. For example, in October 2025, a JetBlue Airbus A320 suddenly nosedived mid-flight over the Gulf of Mexico, injuring 15 passengers and forcing an emergency landing. The cause was a single bit that had flipped in the flight control computer, most likely struck by a cosmic ray. Airbus subsequently recalled around 6,000 aircraft for software updates.^[1]

Although similar instances of radiation damage are not common on Earth, these dangers occur much more frequently in space.

Radiation Damage

One example of a dangerous radiation effect is a single-event upset (SEU). This happens when a charged particle barrels through silicon, ionizing atoms along its path and leaving a wake of electron-hole pairs. If that wake dumps enough charge into a memory cell or flip-flop, the stored bit toggles. The 1 becomes a 0. The satellite thinks the thruster should fire. No permanent damage occurs, but data are compromised.

A single-event latch-up (SEL) is even more damaging. Complementary metal-oxide-semiconductor (CMOS) circuits contain parasitic thyristor structures, accidental silicon-controlled rectifiers hiding in the substrate. A particle strike can trigger these into conduction, creating a low-impedance path from power to ground. When that happens, currents surge, and the silicon heats. Without fast intervention, the device is ruined.

Another danger is the total ionizing dose (TID). Charge accumulates in oxide layers over time, shifting thresholds and increasing leakage. A craft in low Earth orbit (LEO) might experience up to 1 kilorad of TID per year. A craft in geostationary Earth orbit (GEO) many times more—up to 60krad annually. Over a 20-year mission, the higher end of this range would add up to a megarad of accumulated damage.^[2]

The cruel irony is that while shielding helps with TID, it can actually worsen SEU effects. As particles slow down in shielding material, their linear energy transfer increases, meaning they dump charge more densely into whatever they hit next.

Designing for Unpredictable Radiation

Engineers often design for extreme conditions by thinking in terms of mission duration. The level of required radiation hardening scales directly with how long the electronics need to survive. Satellites with different purposes and lifespans demonstrate varying levels of radiation resistance.

One example is CubeSats: standardized nanosatellites meant to last between one and five years.^[3] These are typically made with commercial off-the-shelf (COTS) parts: mass-produced components that are not usually designed for space use.^[4] These components allow for quick production and reduced costs, but they also require significant testing and added radiation shielding to be used in space. Helpfully, if the satellite dies after a year, the data has probably already been transmitted home.

Commercial LEO satellites are meant to have a space life of five to seven years,^[5] and constellation satellites are designed to last about five years in space.^[6] These satellites need the substantial protection that radiation-tolerant (rad-tolerant) components offer.^[7] These parts aren’t originally intended for use in high-radiation conditions but are modified to be rad-tolerant. These modifications typically involve upscreening (i.e., testing commercial or automotive-grade parts beyond their rated specifications to find ones that happen to tolerate radiation better than average), careful shielding around sensitive components, and design margin (i.e., running circuits at less than maximum ratings so they still function as parameters drift).

Deep space probes and GEO satellites sometimes have to survive decades in space.^[8] At this level, radiation-hardened (rad-hard) parts need to be used.^[9] These components are designed for extreme space conditions. Silicon-on-insulator (SOI) processes, error-correcting memory, redundant systems, and components all get tested for the space radiation environment. Every component has to withstand hundreds of kilorads.

Right now, rad-tolerant satellites are where the market is expanding. Thousands of constellation satellites are being launched for broadband, Earth observation, and defense networks. The companies building these constellations want rad-hard performance at something closer to commercial prices. That tension is currently driving most of the innovation.

Current Engineering Approaches

SOI technology has been a workhorse of rad-hard design for decades. Transistors are built in a thin silicon film on top of an insulating oxide layer. This technique eliminates the parasitic thyristor structures that enable latch-up and shrinks the charge collection volume by roughly an order of magnitude compared to bulk silicon. Less volume to collect charge means a particle has to deposit more energy to cause an upset.

Triple modular redundancy (TMR), meanwhile, takes a brute-force approach, where engineers build three copies of every critical circuit, which vote on the outputs. If one gets hit by a particle, the other two circuits outvote it. This works great, but it triples the silicon area, power consumption, and cost.

Recent academic work shows another approach. Researchers at Carnegie Mellon, working with Sandia National Labs, recently demonstrated a rad-tolerant flip-flop fabricated in a 22nm fin field-effect transistor (FinFET) process that achieves TMR-equivalent protection in a smaller area.^[10]

Instead of building three separate flip-flops, the researchers reuse components within a single, more complex structure that provides the same fault tolerance at a fraction of the footprint—42 percent smaller than TMR, according to their testing.^[11] The team won the Best Paper Award at the Design, Automation, and Test in Europe conference in March 2025 and is deploying their design on a CubeSat in 2026.^[12]

Wide-bandgap semiconductors are also changing the equation for power electronics. Gallium nitride (GaN) and silicon carbide (SiC) have wider bandgaps than silicon, which means inherently higher radiation tolerance plus better efficiency at high voltages and temperatures. Recent space validation of rad-hard SiC power devices on the Chinese space station showed a fivefold improvement in power-to-volume ratio and efficiency, jumping from 85 percent to 95 percent compared to silicon.^[13] For power-hungry satellites, that translates directly into mass and thermal savings.

Effects on Earth

Radiation hardening used to mean bespoke chips, ceramic hermetic packaging, and six-figure price tags, but the industry is moving toward plastic packaging, commercial fabs, and academic research labs that can get their designs into orbit within a year of publication.

The same cosmic rays hitting satellites hit aircraft, data centers, and—at lower rates—smartphones. The JetBlue incident is a reminder that radiation effects are real and unforgiving. However, the techniques developed for orbit should filter down. As we depend more on electronics in safety-critical applications, the lessons learned from keeping satellites alive become increasingly relevant on the ground.

Conclusion

Space does not destroy electronics through one grand cinematic failure, but through countless microscopic, almost unseen ambushes. Therefore, designing hardware that survives orbit is not about brute strength alone, but about designing clever architecture, redundancy, and materials that treat every passing cosmic ray as just another nuisance rather than a mission-ending event.

[1] https://www.sidc.be/article/single-event-upset
[2] https://www.laser2cots.com/en/article/25.orbit.html
[3] https://www.nasa.gov/what-are-smallsats-and-cubesats/; https://kupsat.com/technical-foundations-and-lifecycle-of-cubesats-from-manufacturing-to-end-of-use/
[4] https://hubble.com/community/comparisons/why-radiation-hardening-matters-for-satellite-processors-and-what-it-costs/; https://www.laser2cots.com/en/article/5.COTS.html
[5] https://markwideresearch.com/commercial-leo-satellite-market
[6] https://www.space.com/spacex-starlink-satellites.html
[7] https://www.doeeet.com/content/eee-components/radiation-hardened-and-radiation-tolerant-components/; https://hubble.com/community/comparisons/why-radiation-hardening-matters-for-satellite-processors-and-what-it-costs/
[8] https://www.sciencedaily.com/releases/2026/05/260504023835.htm
[9] https://www.doeeet.com/content/eee-components/radiation-hardened-and-radiation-tolerant-components/; https://hubble.com/community/comparisons/why-radiation-hardening-matters-for-satellite-processors-and-what-it-costs/
[10] https://www.ece.cmu.edu/news-and-events/story/2025/04/space-tolerant-computer-chips.html
[11] https://ieeexplore.ieee.org/document/10993214
[12] https://www.ece.cmu.edu/news-and-events/story/2025/04/space-tolerant-computer-chips.html
[13] https://english.cas.cn/newsroom/cas_media/202501/t20250126_899365.shtml

How SiC Is Enabling Next Generation Automotive Power Electronics

Wed, 20 May 2026 16:44:58 GMT

Image Source: KanStockPng/stock.adobe.com; generated with AI

By Vladimir Halaj, Technical Marketing Analyst, onsemi, for Mouser Electronics

EV Power Electronics Challenges and the Role of SiC

Electric vehicles (EVs) impose strict and often competing constraints on power electronics design. Limited installation space, weight targets, efficiency requirements, thermal limits, safety standards, and cost-reduction pressure must all be addressed simultaneously within a vehicle platform expected to operate reliably for many years. As EV architectures evolve toward higher battery voltages and increased onboard power, managing these trade-offs becomes one of the central challenges for OEMs and Tier-1 suppliers.

Silicon carbide (SiC) has emerged as an important wide bandgap (WBG) enabler for addressing these challenges in high-voltage (HV) power electronics. While conventional Si super-junction MOSFETs and IGBTs have served automotive applications well for decades, they show limitations in some applications as power levels rise. These trade-offs affect modern EV performance targets, and they include higher switching losses and constraints on switching frequency set by semiconductor physics, as well as increased cooling overhead and the resulting penalties in size and weight.

These challenges are most visible in the vehicle’s HV power conversion stages, where energy must be converted efficiently between AC and DC or between different DC voltage levels. One such subsystem is the On-Board Charger (OBC), an essential component in every battery electric vehicle. The OBC converts AC power from the grid into DC power suitable for charging the HV battery pack, while operating under tight constraints on efficiency, power density, thermal performance, and electromagnetic compatibility.

OBC requirements vary by vehicle class and regional infrastructure. Premium EVs target onboard charging power of up to 22kW to reduce charging time, driving higher design stress and more complex thermal solutions. EVs in the mid‑price range typically target 11kW, offering more flexibility in power conversion topologies and electronic components selection, thus providing more options between cost and performance. By enabling higher switching frequencies, significantly lowering power losses, providing a low reverse recovery body diode, and improving thermal performance, SiC devices expand the OBC design space. This allows designers to reduce the size of magnetics and passive components, simplify thermal management, and improve overall system efficiency. To support EV performance targets, onsemi offers a broad portfolio of automotive-qualified SiC solutions for OBCs and other high-power EV subsystems. These solutions include discrete SiC MOSFETs, diodes, and integrated power modules that allow designers to scale performance, optimize layout, and meet automotive reliability targets.

OBC Architectures: Power Stage Topologies and Semiconductors

Conventional OBCs are typically implemented as two-stage power converters, consisting of a bridgeless PFC stage followed by an isolated DC-DC stage, commonly based on LLC or CLLC resonant topologies. As EV platforms transition to 800V battery architectures and higher onboard charging power, these stages require SiC devices rated up to 1200V and capable of higher frequency operation.

To support OBC designs in the 11kW to 22kW range, onsemi offers SiC APM32 power modules optimized for both PFC and DC-DC stages. For example, 3‑phase bridge modules, such as the NVXK2VR40WXT2 (1200V, 40mΩ), are well suited for bridgeless PFC implementation, while full-bridge and dual half-bridge modules like the NVXK2TR40WXT address the demands of faster DC-DC conversion (Figure 1). These modules are automotive qualified under AEC-Q101, AQG-324, and meet creepage, clearance, and reliability IEC standards, supporting robust OBC designs in demanding vehicle environments.

Figure 1: Example schematic of a power stage design with APM32 modules for 11kW–22kW OBC solution. Bridgeless PFC topology and LLC topology for DC-DC. (Source: onsemi)

Extending OBC Functionality with Bidirectional Charging (V2H)

Beyond unidirectional charging, modern OBC designs are increasingly expected to support bidirectional energy flow, enabling vehicle‑to‑home (V2H) operation. In this mode, the EV battery can act as a mobile energy storage system, supplying power back to a home during grid outages or when paired with local generation such as solar. From a power electronics perspective, this capability is typically realized using a bidirectional CLLC DC-DC topology combined with an active PFC stage. SiC power modules from onsemi already used in high-efficiency OBC designs are well suited to support these bidirectional operating modes, enabling efficient, compact implementation and seamless transitions between charging and discharging operation.

Optimizing OBC Designs with Top-Side Cooled SiC MOSFETs

In 400V battery architectures, OBC designs are increasingly challenged by rising power density targets, tighter thermal limits, and the need for high efficiency across a wide operating range. To address these requirements, SiC MOSFETs are becoming the preferred switching devices in both OBC power stages and other HV DC‑DC converters.

To support these demands, onsemi has introduced advanced SiC MOSFETs in a top-side cooled T2PAK package. Compared to conventional bottom-cooled packages, T2PAK enables direct thermal contact between the device’s exposed drain pad and an external heatsink or metal chassis (Figure 2). This significantly improves heat extraction from the die, reduces thermal stress on the PCB, and enables higher continuous power operation within the same footprint. As a result, designers can achieve higher power density while maintaining robust thermal margins, an increasingly critical requirement in compact OBC enclosures.

Figure 2: SiC MOSFETs in a top‑side cooled T2PAK package enable direct thermal contact between the device’s exposed drain pad and an external heatsink or metal chassis (Source: onsemi)

Achieving peak system performance requires careful attention to the complete thermal stack-up, including heatsink, mounting pressure, and the selection of high-conductivity thermal interface material (TIM). Proper TIM application ensures consistent thermal resistance beyond the device’s junction-to-case resistance (R_ƟJC), supporting long-term reliability under harsh operating conditions (Table 1).

Table 1: Key specifications of onsemi SiC MOSFETs in T2PAK package

Part Number	V_DSS	V_{GS_OP} [V]	R_DS(ON) [mΩ]	Q_G(TOT) [nC]	R_ƟJC [℃/W]
NVT2012N065M3S	650V	-3 / +18	12.7	135	0.35
NVT2016N065M3S	650V	-3 / +18	16	100	0.45
NVT2023N065M3S	650V	-3 / +18	23	74	0.52

In addition to thermal advantages, the T2PAK package minimizes parasitic stray inductance by eliminating long leads and enabling tighter commutation loops compared to traditional D2PAK or TO-247-4L packages. This design feature enables more flexible electrical routing on the PCB and directly contributes to reduced switching losses, reduced voltage overshoot, and higher overall system performance. Combined with onsemi’s M3S SiC technology, top-side-cooled SiC MOSFETs provide a compelling solution for high-performance OBC designs in 400V EV platforms.

From Devices to Systems: Building SiC‑Based Solutions

To fully leverage the benefits of SiC MOSFETs, galvanically isolated gate drivers must be optimized for this technology, including fast switching capability and robust protection. SiC MOSFETs are susceptible to parasitic turn-on due to Miller capacitance C_DG, which couples drain voltage to the gate during switching events. This can occur during the MOSFET turn-off phase due to the remarkably high di/dt, and subsequently lead to shoot-through currents and device failure if a direct short from the high-voltage rail to ground appears during the parasitic turn-on. One highly effective mitigation against this issue is to swing V_GS below 0V, typically down to -3V or even -5V during the turn-off phase. The NCV51152 isolated gate driver enables this protective feature and can generate a negative V_GS swing during turn-off by supporting an external negative bias or a negative power supply.

These system concepts come together in onsemi’s 11kW Matrix OBC demonstration design, which shows how SiC technologies can be combined into a complete OBC solution (Figure 3).

Figure 3: onsemi’s 11kW Matrix OBC demonstration design (Source: onsemi)

SiC MOSFETs in top-side cooled T2PAK packages form the core of the power stage, enabling switching performance, efficient thermal management, and robust implementation. When paired with galvanically isolated gate drivers, the design achieves robust control, fast switching, and reliable operation. This demonstration design highlights a system-level approach, showing how advanced semiconductors, packaging, thermal management, and control algorithms can be integrated into a working OBC platform that addresses real EV design constraints.

Author Bio

Vladimir is a technical marketer at onsemi specializing in automotive and power electronics solutions. He brings a background in electronics and hardware design and holds a university degree in electrical engineering, specializing in electronics and photonics.

Why TOLL-8N Is Gaining Momentum in High-Power, High-Density Designs

Mon, 18 May 2026 19:43:54 GMT

(Source: danter /stock.adobe.com)

For electronic engineers, device packaging is just as critical to performance and thermal management as the die or multichip assembly it contains. This is especially true as gallium nitride (GaN) power devices continue to gain adoption, placing renewed emphasis on packaging as a key factor in unlocking their full performance potential. Even small parasitic elements—such as stray inductance, capacitance, and resistance within the package—can significantly affect circuits switching higher voltages and currents at faster slew rates. As a result, engineers cannot afford to overlook the importance of optimized packaging.

This blog examines why packaging is increasingly important for 650V GaN devices and how the innovative TOLL-8N package helps enhance the performance of high-speed, high-voltage field-effect transistors (FETs) while addressing parasitic effects and thermal limitations.

Start with LCR Basics

The impact of parasitics can be understood through a simple equation that defines the relationship between inductance (L) and the rate of change of current $\frac{{di}^{}}{dt}$ :

V (t) = L $\frac{{di}^{}}{dt}$

The use of GaN FETs does not change the basic physics. However, their extremely fast current and voltage switching ( $\frac{{di}^{}}{dt}$ ) means that even small parasitic values once considered negligible can now have a pronounced effect on circuit waveforms. In actual hardware, these parasitics can lead to issues such as increased power-device drain overshoot and ringing, gate bounce that may cause false turn-on, and higher electromagnetic interference (EMI) peaks.

Such effects are often missed in simplified simulations. Accurate predictions typically require nonlinear device models or explicit extraction and inclusion of parasitic elements.

Identifying the locations, types, and values of all parasitics is no simple task. Although these parasitic values are very small, their impact on circuit behavior can be substantial. They are also difficult to physically access, measure, and verify.

Many of the most harmful parasitics arise from board layout, probing techniques, grounding, and copper geometry. While these elements lie outside the direct control of the power device itself, they strongly influence the measurement process. Further complicating matters is that many parasitic parameters are not fixed, as they are with discrete inductors or capacitors, but instead can vary depending on operating conditions such as drain-source voltage (V_DS).

What Changes at 650V Compared to Lower-Voltage Switching

As voltages rise from lower ranges, such as 80V to 200V and up to 650V, some design factors scale predictably while others do not. Higher power-rail voltages make devices more sensitive to overshoot, since there is less margin as the voltage approaches the V_DS rating. At the same time, faster switching speeds and sharper edges increase the voltage induced by $\frac{{di}^{}}{dt}$ across any inductance. As a result, gate-drive techniques that may be sufficient at lower voltages cannot simply be scaled up–as device behavior changes with voltage and current.

Package parasitics set a practical upper limit on power-device performance. Just a few nanohenries (nH) of DC-link or commutation loop inductance can interact with circuit capacitances to produce ringing and drive V_DS into potentially destructive overshoot during turn-off. In addition, common-source inductance (CSI) can distort the gate-source voltage (V_GS), while gate-loop inductance feeds back to alter the effective input impedance seen by the driver, distorting the driver-current waveform.

The effects of fast dv/dt slewing can be especially problematic because they pump current through the power FET’s Miller capacitance. If the gate feedback loop has a loose time constant, which is often necessary for functional reasons, brief gate-source glitches may be enough to trigger shoot-through.

Rapid $\frac{{dv}^{}}{dt}$ creates displacement current through the gate-drain (Miller) capacitance. If the off-state gate path impedance is too high, or if CSI raises the source potential, the gate of the complementary switch in a half-bridge can momentarily exceed the threshold voltage and cause false turn-on. This leads to shoot-through, a condition where both the high-side and low-side FETs conduct simultaneously, creating a low-impedance path directly from the power supply to ground. The resulting high-current spikes are severe enough to damage or destroy the switches.

Go Kelvin

Engineers familiar with high-precision test and measurement understand the value of four-wire Kelvin connection. This technique is used to eliminate measurement error caused by voltage drops from current flowing through wires and other resistive elements connected to the device under test (DUT).

In a Kelvin configuration, two conductors supply current to and from the DUT, while a second pair connects directly to the DUT terminals to sense voltage. Because these sense leads carry virtually no current, they experience no resistive voltage drop, allowing for more accurate voltage measurement (Figure 1).

A variation of the four-wire Kelvin connection is used in many power GaN packages to improve switching performance. In this implementation, an additional Kelvin source lead is included to provide a dedicated, low-return path for the gate-drive circuit. By isolating the gate-source sensing path from the high-current power source return, this approach enables more precise control of the power device.

Figure 1: Schematic diagram of a power MOSFET with Kelvin source. (Source: ROHM Semiconductor)

Using a Kelvin connection minimizes the inductive voltage fluctuations that would otherwise occur in the primary current-carrying path by decoupling the gate-drive return from that path. This significantly reduces CSI that would otherwise appear as negative feedback on the gate signal. Such feedback is detrimental because it opposes the action of the gate driver, increasing switching losses and potentially contributing to oscillation.

Packaging Impacts on Cooling

If minimizing package and printed circuit board parasitics were the only concern for device designers, the challenge would be more straightforward. However, packaging must also serve as the thermal pathway, conducting heat from the internal die to the external environment where it can be dissipated and removed.

Cooling is typically accomplished by some sort of heat-sink structure that draws heat away from the localized source. This is often supplemented by natural convection or forced-air cooling, such as a fan, to further reduce temperature within the board and enclosure. As with parasitic effects, the thermal behavior of an integrated circuit (IC) die within its package can be complex and requires careful consideration.

Several factors influence heat flow and dissipation, but designers typically begin by focusing on two key parameters:

θ_JC: Thermal resistance from the die junction to the case. This is often divided into case-top and case-bottom values, making it a useful first-order metric for comparing different package options.
θ_JA: Thermal resistance from the junction to ambient, often separated into top and bottom paths and represents the resistance from the package case to the surrounding air. It is especially important when evaluating convection cooling and, unlike θ_JC, does not include an external heat sink.

Minimizing parasitics and thermal resistance are closely linked aspects of package design. For example, flip-chip construction can reduce the wire bonding impedance to improve efficiency while also lowering thermal resistance from die to IC pins. Larger solder paste areas and lead-frame structures can provide similar benefits, although these improvements may be limited by overall package constraints.

Once heat reaches the outside of the package, additional design measures can further improve dissipation. These include increasing copper area and thickness under and around the package, adding thermal vias to spread heat to other PCB layers, and attaching heat sinks directly to the package.

TOLL-8N Package Makes a Difference

The choice of power device packaging has a considerable impact on PCB layout and can strongly influence package-to-board parasitics. To address the growing need for both lower thermal resistance and package parasitics, power device vendors are adopting advanced package technologies.

One example is the TOLL-8N surface-mount package used for ROHM Semiconductor’s GNP2070TD-Z, a 650V enhancement-mode GaN high-electron-mobility transistor (HEMT) (Figure 2). The device offers 70mΩ on-resistance and 5.2nC gate charge in a compact 11.68mm × 9.9mm × 2.4mm package, making it ideal for high switching-frequency and high-density converter applications.

Figure 2: ROHM’s GNP2070TD-Z 650V enhancement mode GaN HEMT, featuring the TOLL-8N package and contact layout. (Source: ROHM Semiconductor)

The 8-lead surface-mount TOLL-8N (TO-Leadless) package (Figure 3) provides shorter current paths and lower lead inductances than through-hole devices. Along one edge, eight terminals are arranged to support three functions: one gate contact, one dedicated Kelvin source contact, and six source contacts. Distributing the source connection across six leads reduces parasitics, current density, and thermal resistance. On the opposite edge, a single wide drain contact provides similar electrical and thermal benefits.

Figure 3: Cross-section of the internal connections of the GNP2070TD-Z package. (Source: ROHM Semiconductor)

TOLL-8N is one of several package options used for power devices. Other common types include the surface-mount DFN8080 and through-hole TO-247. Table 1 compares the key attributes of these three packages against major design-in criteria.

Table 1: Relative comparison of key package attributes for TOLL-8N, DFN8080, and TO-247 power-device packages. (Source: ROHM Semiconductor)

Attribute	TOLL-8N (TO-Leadless, SMT power)	DFN8080CK (8×8, SMT DFN/LGA)	TO-247 (through-hole, heat sink-mounted)
Primary fit	SMT-friendly high-power density; supports robust current handling	Smallest footprint; enables very compact, fast-switching layouts	High-power builds with straightforward heat sink mounting
Assembly /service	Reflow SMT; moderate rework difficulty	Reflow SMT; hardest rework (small pads)	Through-hole + heat sink hardware; easiest field replacement
Dominant thermal path	PCB copper/vias (often primary)	PCB copper/vias (most sensitive)	Case-to-heat sink (primary)
Parasitics & switching behavior	Generally lower than through-hole; benefits from multi-source terminals	Can be lowest with excellent layout; highly layout-dependent	Higher lead/package inductance; more overshoot/ringing risk at fast edges
Gate reference options	Often includes Kelvin source (device-dependent)	Device-dependent; may rely on tight layout or dedicated sense pin	Device-dependent; 3-lead common, some Kelvin/4-lead variants exist
Process sensitivity	Needs good solder/void control on thermal/current pads	Tightest process window (voiding, coplanarity, pad design)	Mechanical interface variation (TIM, torque, flatness) often dominates
Best use cases	Dense AC/DC or DC/DC where SMT + power handling are both required	Ultra-compact high-frequency stages with strong PCB thermal design	Designs prioritizing heat sink simplicity/serviceability over max switching speed

Conclusion

As power devices push towards higher voltages, currents, and performance levels, driven largely by advances in GaN technology, package parasitics and thermal characteristics are becoming increasingly critical to unlocking the devices’ full capability. Packages such as TOLL-8N reduce these detrimental effects compared to conventional alternatives. As a result, switching devices like ROHM Semiconductor’s GNP2070TD-Z, a 650V enhancement mode GaN HEMT, benefit from the capabilities of the TOLL-8N package to maximize performance.

Author

Bill Schweber is a contributing writer for Mouser Electronics and an electronics engineer who has written three textbooks on electronic communications systems, as well as hundreds of technical articles, opinion columns, and product features. In past roles, he worked as a technical website manager for multiple topic-specific sites for EE Times, as well as both the Executive Editor and Analog Editor at EDN. At Analog Devices, Inc. (a leading vendor of analog and mixed-signal ICs), Bill was in marketing communications (public relations); as a result, he has been on both sides of the technical PR function, presenting company products, stories, and messages to the media and also as the recipient of these. Prior to the MarCom role at Analog, Bill was associate editor of their respected technical journal, and also worked in their product marketing and applications engineering groups. Before those roles, Bill was at Instron Corp., doing hands-on analog- and power-circuit design and systems integration for materials-testing machine controls. He has an MSEE (Univ. of Mass) and BSEE (Columbia Univ.), is a Registered Professional Engineer, and holds an Advanced Class amateur radio license. Bill has also planned, written, and presented online courses on a variety of engineering topics, including MOSFET basics, ADC selection, and driving LEDs.

Powering Lanthanide Nanoparticles for NIR II LEDs and Photonics

Sat, 16 May 2026 00:25:30 GMT

(Source: lurii/stock.adobe.com; generated with AI)

Picture a class of nanoparticles that emit light so pure and stable they make quantum dots seem sloppy. Nanoparticles that emit light at wavelengths capable of penetrating deeply through biological tissue, including flesh and bone.

These wavelengths are so narrowly defined they sit comfortably inside the fiber-optic bands already used to shuttle vast amounts of data at near-light speed. Bands where just a few nanometers of drift make the difference between clear signal and noise.

There’s just one snag. These nanoparticles are electrical insulators, and trying to power them is like trying to fill a sealed bottle by pouring water onto it.

Seemingly impossible, right? Turns out, that’s wrong.

A team of researchers at the University of Cambridge’s Cavendish Laboratory figured out how to crack this problem^[1] and get the hypothetical “water” inside the sealed bottle using lanthanide emitters, effectively powering an electrical insulator with the potential to significantly reshape medical imaging. In this blog, we trace the physics that makes lanthanide light so narrow, the reason NIR‑II travels farther through tissue than visible wavelengths, and the deceptively simple molecular bridge that turns an insulating nanoparticle into something you can actually drive like a light-emitting diode (LED).

What Makes Lanthanide Nanoparticles Different

Before we unpack the problem solved by the Cambridge team, let’s rewind a bit and talk about the nanoparticles themselves.

Lanthanides are a group of elements, such as neodymium, erbium and ytterbium, that have a rather unusual electron configuration. When you embed or “dope” their ions into a crystalline nanoparticle host, they’re able to emit that pure, stable light with all its remarkable properties.

The clarity of this light can’t be overstated. It’s the equivalent of a single voice hitting perfect pitch in a choir of different and often dissonant wavering notes. This clarity of light comes out at a highly specific narrow wavelength rather than a broad smear of colors and frequencies.

The Second Near‑Infrared Window (NIR‑II)

This narrow wavelength is known as the second near-infrared window, or NIR-II, and it spans roughly 1,000nm to 1,700nm.

Biological tissue is surprisingly transparent at those wavelengths. While most visible light gets scattered and absorbed within mere millimeters of entering a body, NIR-II light can penetrate 10–20mm with micrometer-scale resolution.

To put it in visual terms, it’s the difference between trying to see through fog and looking through slightly tinted glass. The difference is massive. Imagine how this might revolutionize medicine when medical professionals are able to use NIR-II to visually slice through deep tissue to see tumors, track organ function, and guide surgery without having to make any incisions.

Hitting an 8‑Electron‑Volt Wall

Back to the issue of how to power these electrical insulators, however. The crystalline hosts holding the lanthanide ions have bandgaps around 8eV. For context's sake, silicon sits at about 1.1eV. At 8eV, electrons simply bounce off that bandgap like a wall. Until recently, the only way scientists could make these nanoparticles glow was to bombard them with an external light source, making it cumbersome—if not impossible—to build compact and electrically driven devices.

Stop Forcing Charge—Move Energy Instead

The Cambridge researchers found a novel way around that bandgap wall.^[2] Instead of trying to force charge through an impenetrable barrier, they wrapped the nanoparticles with organic molecules that could accept electrical energy and transfer it inward by a different mechanism. This approach is like relaying a message into a soundproof room via an intermediary, rather than shouting through the walls.

Although demonstrated with lanthanides, the underlying mechanism is not material-specific.

In this case, the intermediary is a molecule called 9-anthracenecarboxylic acid (9-ACA). It's an organic dye that chemically anchors itself to the nanoparticle's surface. The molecule absorbs energy and enters what’s called a “triplet excited state.”

Triplet States: From Optical Waste to Hidden Pathway

Typically, triplet states are considered waste. Quantum mechanical rules make them “dark,” meaning they can't release their energy as light efficiently; therefore, most optical systems treat triplet energy as lost heat.

Lanthanide ions, however, don’t play by the rules. The triplet energy transfers from the organic molecule to the lanthanide ion inside the nanoparticle with over 98 percent efficiency,^[3] and it comes out as pure, narrow-wavelength NIR-II light.

Turning Dark States into Light

The elegance of this solution is breathtaking. Like discovering that exhaust heat from your car could actually be captured and converted into electricity. The Cambridge team's solution turned discarded waste from optical systems into an entire mechanism that made impossible LEDs possible.

Even the first-generation devices resulting from this eccentric system are impressive. The LnLEDs (as the team calls them) operate at around 5V, which is somewhere within USB power territory.

They emit light with spectral linewidths as narrow as 20 nanometers, depending on the lanthanide used. For comparison, quantum dots in the near infrared typically achieve 100nm or broader. You may think that's not a huge difference at nanometer scale, but it is.

The narrower emission results in a markedly cleaner signal, meaning less interference between channels in optical communications and far better specificity for medical sensing. The current efficiency sits at around 0.6 percent,^[4] which may sound modest by mature LED standards, but it's genuinely promising for devices built from materials that couldn't be electrically powered at all until now.

Pushing the Breakthrough Forward

While the results of this novel nanoparticle solution may sound too good to be true, it's important to note that no less than two independent research teams arrived at essentially the same solution within just weeks of each other. While Cambridge was developing their approach, another collaboration of academics from Singapore, China and Hong Kong had been pursuing the same challenge for over 14 years, with Professor Liu Xiaogang of the National University of Singapore describing the early years as “chasing light trapped inside a stone.”

The breakthrough may not be limited to lanthanides alone. Scientists from the Cambridge team have noted that “countless combinations” of previously off-limit organic molecules and insulating nanomaterials are now worth exploring as electrical driving materials. The physics barrier to powering the previously un-powerable has shifted, opening up real possibilities for a brand new class of photonic devices, from wearables and denser optical networks to cutting-edge medical imaging.

The hard part was proving it could be done at all. Now it has. What needs to follow is iteration, optimization, and the slow work of turning a proof of concept into something engineers can actually build with. And that part is where all the fun and creativity resides.

Conclusion

For years, lanthanide nanoparticles have been a remarkable light source trapped behind an electrical wall. The moment scientists learned to move energy across that wall through molecular intermediaries, those nanoparticles stopped being laboratory curiosities and have started to look like the foundation of a whole new class of devices—poised to reshape applications such as medical imaging, optical communications, and next‑generation photonics in genuinely groundbreaking ways.

[1] ;https://www.phy.cam.ac.uk/news/tiny-antennas-to-bring-electrical-power-to-the-un-powerable-nanoparticles/
[2] https://www.nature.com/articles/s41586-025-09601-y
[3] https://www.phy.cam.ac.uk/news/tiny-antennas-to-bring-electrical-power-to-the-un-powerable-nanoparticles/
[4] https://www.phy.cam.ac.uk/news/tiny-antennas-to-bring-electrical-power-to-the-un-powerable-nanoparticles/

A Tiny Component with a Large Impact on EV Charging

Thu, 30 Apr 2026 22:32:47 GMT

(Source: The Stock Photo Girl/stock.adobe.com; generated with AI)

To promote the changeover from internal combustion engine vehicles to electric vehicles (EVs), governments and regulatory entities around the world are expanding the rollout of charging infrastructure as quickly as possible. That urgency is placing great demands on infrastructure providers, who are simultaneously responding to demands for higher-powered chargers.

In locations such as the European Union (EU), fast charging is being mandated by law; meanwhile, consumers are the driving force in other locations. The International Energy Agency (IEA) estimates that the total number of public chargers increased to over 5 million in 2024, the same year in which the number of fast chargers (22kW–150kW) reached 2 million, and ultra-fast chargers (150kW+) grew by over 50 percent.^[1] Another complex layer for infrastructure providers is the increasing demand for bidirectional charging. These trends are ongoing and likely to accelerate.

This blog explores why charger control circuitry for various types of EVs (collectively known as xEV) faces growing signal integrity and isolation design challenges as charging infrastructure scales, form factors shrink, power levels rise, and reliable Power Line Communication (PLC) becomes central to international charging standards. Then, we explain how pulse transformers are engineered to preserve PLC performance, provide isolation, and enable reliable communication in modern xEV charging systems.

Why Control Circuits in EV Chargers Are Uniquely Demanding

Much of the discussion around EV chargers focuses on the power electronics that support increasing power levels, but the control circuitry driving power electronics is the key for reliable performance. EV chargers have two main sections: the power stage handles energy conversion, while the control stage ensures the charging process is carried out safely and efficiently.

The control signal can be delivered as a separate communication interface or via PLC, where data is carried over the Control Pilot (CP) line within the charging interface. This delivery method avoids the need for a separate dedicated data cable within the charging interface and helps reduce system complexity, weight, and connector count.

Both the North American Charging Standard (NACS) and Combined Charging System (CCS) standards use PLC for charging. Standards such as ISO 15118 define the electrical and communication requirements for PLC-based charging, including signal strength and noise tolerance, which directly impact control circuit design.^[2] The design process is further being challenged due to the ongoing standards convergence to allow the vehicle to automatically identify itself and negotiate charging in an easy plug-and-charge process.

Ensuring the quality of the control signal is vital for charging and is also integral to meeting relevant standards for certification. A weak control signal, or one affected by interference, can lead to failures in managing the charging session and stop the charger from communicating with the battery management system (BMS). Every component, wire, or connector in the control line introduces insertion loss, which attenuates and distorts the broadband PLC signal. There are larger insertion losses at higher frequencies that do affect PLC communications in the 2MHz to 30MHz range.

In addition to the signal degradation, there are other threats to signal integrity. The current trend to reduce charger size means that the control and power electronics share a smaller circuit board. To make designs more power-dense and efficient, wide bandgap (WBG) electronics are often used. These devices switch large amounts of current very quickly, which can cause significant electromagnetic interference (EMI) in a frequency range similar to PLC. Additionally, fast transients and variable cable impedance can affect control signal integrity.

The Value of Pulse Transformers

Dealing with control signal quality challenges makes the pulse transformer one of the most important components in the charging process. These devices use magnetic coupling to rapidly transfer high-speed rectangular pulses between circuits with minimal distortion. In an EV charger, they preserve the integrity of the control signal while providing the galvanic isolation that protects the control circuit from the power circuit and EMI (Figure 1). Pulse transformers can also be useful for blocking the DC component of the signal and suppressing common-mode noise. Other options for performing these tasks are less effective, and they involve making a trade-off between frequency behavior and noise immunity.

Figure 1: Pulse transformers are vital in a PLC circuit to preserve signal integrity and protect the control circuit from the high-power circuit and noise. (Source: TDK)

In order to minimize signal degradation, pulse transformers in EV charging applications must maintain low insertion loss across the full 2MHz to 30MHz transmission bandwidth.

While several transformer topologies can meet these electrical requirements, toroidal-type pulse transformers are commonly used in PLC communication circuits. However, their traditional manual winding process can make it difficult to achieve consistent winding quality. Furthermore, to withstand high voltages, they are often coated with resin, further increasing both size and cost.

A New Approach to Pulse Transformer Design

In PLC-based EV charging control circuits, pulse transformers are designed for signal performance instead of traditional power-stage isolation. Fully automated winding techniques improve consistency and reduce variability, which helps minimize insertion loss. These approaches also support smaller form factors and more cost-effective manufacturing compared to manually wound designs.

In addition, ferrite selection and winding geometry can be engineered to maintain low insertion loss across the full 2MHz to 30MHz PLC frequency range. For xEV PLC applications, removing unnecessary insulation further reduces size and parasitic effects, without compromising performance, since control circuits do not require the same isolation levels as high-power components connected directly to the grid.

AMT45S Pulse Transformers in xEV Charging Control Circuits

The AMT45S from TDK is a pulse transformer that has been designed specifically to meet the needs of PLC communications in EV charging applications. It is manufactured using fully automated winding technology, and the lack of a resin coating helps reduce the size and make these transformers more cost-effective than other solutions. The ferrite and winding geometry have been developed from the ground up to provide the lowest possible insertion loss across the whole 2MHz to 30MHz frequency band (Figure 2).

Figure 2: The TDK AMT45S shows a remarkably low insertion loss across the whole PLC frequency range. (Source: TDK)

The AMT45S pulse transformer is engineered to be as reliable as possible over a long operating lifetime. Its small footprint makes it ideal for use at the center of noise-resilient control layouts. The device is also suitable for use in both on-board chargers and in charging stations. To support design integration, the device has been validated with multiple PLC chipsets, including Qualcomm’s QCA series and Lumissil’s IS32CG family.

Conclusion

As EV charging infrastructure continues to scale, the reliability of control‑circuit communication has emerged as a defining factor in overall charger performance. Preserving PLC signal integrity amid higher power levels, tighter layouts, and increased EMI requires careful attention to every element in the communication path, making pulse transformers a critical enabler rather than a supporting detail. Purpose‑built solutions like TDK’s AMT45S show how advances in transformer design—through low insertion loss, effective isolation, and compact form factors—can directly support standards‑compliant, noise‑resilient PLC communication in modern xEV chargers.

With charging systems continuing to evolve, it is becoming increasingly clear that the future of fast, reliable EV charging depends not only on how efficiently power is delivered, but on how cleanly and consistently control signals are carried alongside it.

Author

Since graduating with a BSc in Electronic Systems from the University of the West of Scotland in 1997, Alistair Winning has worked in electronics media across marketing, PR, and journalism roles. During that time, he worked as the editor of Electronics Engineering, Embedded Systems Europe, EENews Embedded, Technology First, Electronic Product Design and Test, and Panel Building and Systems Integration magazines. Currently, Allistair is the European Editor of Power Systems Design and a freelance writer, specializing in electronics and engineering.

[1] https://www.iea.org/reports/global-ev-outlook-2025/electric-vehicle-charging
[2] https://www.iso.org/standard/77845.html

Mitigating Growing EMI Challenges from High-Efficiency Power Systems

Mon, 23 Mar 2026 18:08:13 GMT

As applications for variable speed motors and battery charging become more widespread, conducted EMI is also increasing, but there are solutions.

(Source: Audrius Merfeldas/stock.adobe.com)

Around 2020, Tesla stopped putting AM radios in its vehicles. Tesla and other makers of electric vehicles (EVs) asserted that electrical noise from high-frequency switches and electronic equipment built on wide-bandgap semiconductors ruined reception.^[1] Conventional FM radios are less severely affected, but they are also being phased out.^[2]

Electromagnetic interference (EMI) can be an annoyance to radio listeners, but in industrial environments, EMI problems are increasing as today’s power systems scale up to improve efficiency. On this larger scale, the effects are more damaging than poor reception.

Today’s power systems are designed for efficiency. A common tactic is the use of variable-frequency drives for motors, allowing speeds to be optimized while minimizing power consumption. Such systems increasingly depend on silicon carbide (SiC) and gallium nitride (GaN) components rather than traditional silicon, due to their wide-bandgap characteristics, which permit better performance in high-voltage, high-temperature, and high-frequency applications. The result is lower power consumption and higher power density, which are important in challenging applications such as EVs.

Electronic equipment used in these applications must be tested for electromagnetic compatibility (EMC) in accordance with multiple standards and protocols. These testing methods also evaluate EMI characteristics. Passing EMC is typically required for market access and helps reduce the risk of interfering with nearby equipment and infrastructure.

This blog discusses how high-efficiency power conversion using SiC and GaN devices is increasing conducted EMI in modern industrial and energy systems, and how proper front-end filtering helps mitigate those effects.

High Efficiency as Baseline

Designing electrical equipment involves balancing complex trade-offs, with market forces determining priority. Modern design cycles frequently prioritize early optimization for power level, efficiency, cost, and power density. This is understandable, but it deprioritizes EMI concerns. The highest practical switching speeds are applied for each type of transistor, SiC for its high power handling and GaN for its high speeds. Designers push these to their edge rates to deliver maximum performance, always trying to squeeze out more efficiency, thermal margin, and power density to reach platform-level performance targets. Some EMI-minimizing mechanisms are built in, but they stop short of impacting performance. When the desired characteristics are optimized, producers hope that the product will still pass EMC testing.

The basic architecture of a system and its resulting current paths determine how conducted EMI propagates. When currents flow through circuit imbalances or certain parasitic circuit elements, it creates conducted EMI. This type of interference can also be created by PC board trace inductances and capacitances. The resulting noise can couple to other areas of the circuit magnetically (inductive) or electrically (capacitive).

The following design choices can influence these effects:

Power stage topology—The arrangement of switches, diodes, inductors, etc., for efficient power conversion.
DC-link and input network structure—The intermediate stage that decouples the primary source from downstream power-conversion stages.
Cable length, grounding scheme, and enclosure design—Good configuration choices minimize undesired output.

Once designers make these choices, correcting for their effects later via local tuning becomes very difficult. Careful choices early on are critical.

How EMI Results from High-Efficiency Designs

EMC testing labs (Figure 1) closely examine equipment. While they cannot determine the equipment’s efficiency during a test, they can draw conclusions from the configuration about how much EMI a given design is likely to generate.

Figure 1: EMC testing labs quantify both conducted and radiated EMI from subject devices. (Source: Kzenon/stock.adobe.com)

Designers often undermine their own efforts by raising switching frequencies to achieve higher efficiency. However, pushing frequencies to edge rates to reduce switching losses increases the noise’s spectral bandwidth. Unfortunately, some frequency ranges and their harmonics cause problems with other types of equipment, including various medical devices. EMC testers are mostly concerned with frequencies between 150kHz and 30MHz for conducted EMI, as these frequencies cause the greatest interference with specific classes of consumer, medical, and industrial equipment.

Parasitics also create EMI. Circuit designers understand the relationship between switching speed and EMI. But layout and packaging parasitics can create unexpected resonance and coupling paths that amplify both common-mode and differential-mode emissions. As switching speed increases, other elements of the physical system can further increase EMI levels. These parasitic sources take a variety of forms, including coupled traces/loops, position of individual components, power cable type and routing, and enclosure design.

These items and interactions act as inductive and capacitive elements when placed in high-frequency switching circuits. For example, the internal transformer in a DC-DC converter can couple to a nearby PCB trace, inducing a current at the converter’s frequency. These parasitics shape how switching noise couples to input lines, but the effect can be difficult to predict because so many elements come into play. Small differences in the positioning of individual components on the PCB can create or eliminate such coupling, as can cable positions. Interactions are difficult to predict, but guidelines exist for avoiding some recognized sources.

Challenges and Mitigation Approaches

The ability to utilize today’s variable-voltage and variable-frequency systems has delivered substantial energy savings across many applications. Such sophisticated power management is available in high-incidence areas such as variable-speed motor drives, HVAC and climate-control systems using heat pumps, and charging infrastructure for EVs.

These all have similar basic operational characteristics:

Fast switching and high power levels to maximize efficiency
Three-phase plus neutral power distribution
Elevated common-mode EMI where current flows in one direction using a neutral or earth to complete the circuit (EMI is driven heavily by parasitics)
Elevated differential-mode EMI where current flows in both directions (EMI is driven by line impedances)

When creating a new piece of equipment from scratch, it is possible to incorporate EMI mitigation strategies early on, although this may require multiple prototyping stages. But later in the process, one must find ways to reduce EMI from existing equipment or new installations. Where there is no opportunity to modify the equipment itself, the more practical solution is a system-wide approach with an appropriate filter on supply lines to isolate the equipment and protect other applications farther upstream. To mitigate conducted emissions from moving into the supply, such solutions call for system-level filtering capable of handling a neutral.

Prime examples of effective filtering architecture include the TE Connectivity/Schaffner FN3297 and FN3298 filter series. These filters, engineered for industrial automation and climate control systems, provide robust conducted EMI mitigation for three-phase plus neutral systems. Designed for 480V_AC nominal operation, they support current ratings from 8A to 36A, have short-circuit current rating (SCCR) of 100kA, and comply with IEC and UL standards. The filters feature compact construction, front wiring, and withstand surge levels up to 4kV (L-PE) with high insulation resistance.

Conclusion

Efficiency gains from wide-bandgap-based equipment can be substantial, although conducted EMI effects often remain troublesome. However, once appropriate mitigation strategies have been adopted, they remain in place and do not normally create ongoing costs. Effective filtering, as offered by TE Connectivity/Schaffner products, provides practical, cost-effective solutions for systems, helping companies maximize efficiency gains.

Author

Peter Welander, now semiretired, has been working as a freelance writer and editor for more than 10 years, following seven years as a senior editor and content manager for Control Engineering magazine. During this time he has written heavily about industrial automation, primarily in process industries. Responsibilities have also included audio and video production, podcasts, and blogging.

Moving into the publishing world followed many years working in sales and marketing management, engineering, and operations for a variety of industrial manufacturers. One capability that he has had throughout his career is the ability to grasp technical concepts and explain complex ideas clearly. His personal interests include photography, a machine shop, woodworking, and pipe organ building.

[1] https://spectrum.ieee.org/am-radio-ev-interference
[2] https://www.ceoutlook.com/2026/01/15/car-makers-remove-am-fm-what-it-means-for-12-volt/

New Tech Tuesdays: Radiation-Hard GaN RF Advances LEO Satellite Connectivity Performance

Tue, 17 Mar 2026 05:01:00 GMT

New Tech Tuesdays

Join Mouser's Technical Content team for a weekly look at all things interesting, new, and noteworthy for design engineers.

The “New Space” era is no longer a concept but a bustling reality, dominated by massive low Earth orbit (LEO) satellite constellations. These constellations are the backbone of the integrated 5G and nascent 6G networks, promising to bridge the digital divide by delivering high-speed, low-latency connectivity to the most remote corners of the globe. However, the hostile environment of space remains a formidable barrier. To survive in such harsh conditions and deliver reliable performance, the radio frequency (RF) systems driving these connections rely on advanced materials like gallium nitride (GaN) and robust power management solutions.

This week’s New Tech Tuesdays explores the critical intersection of radiation-hardened electronics and next-generation connectivity by demonstrating how LEO constellations leverage GaN-based RF amplifiers to maintain vital links while withstanding cosmic radiation.

GaN and LEO Connectivity

Integrating LEO satellites with terrestrial networks is essential for meeting the “connecting the unconnected” goal of 5G and beyond.^[1] Unlike geostationary (GEO) satellites, LEO constellations operate at lower altitudes of 300km to 2000km, which significantly reduces latency, a key performance indicator for vertical domains such as the Industrial Internet of Things (IIoT), remote eHealth monitoring, and intelligent vehicular networks.^[2] However, to achieve the necessary data throughput and connectivity density, these satellites require high-performance RF systems capable of handling high power and wide bandwidths. This is where GaN technology becomes indispensable.

Compared to traditional gallium arsenide (GaAs) or silicon solutions, GaN offers superior power density and efficiency. According to recent studies, GaN’s high electron mobility facilitates rapid charge transport, which significantly reduces switching and conduction losses—a prerequisite for high-frequency operations in power-constrained satellite systems.^[3] It also enables solid-state power amplifiers (SSPAs) that are smaller, lighter, and more efficient, which are critical factors for satellites’ weight and power budget constraints.

Furthermore, GaN boasts a wide bandgap of approximately 3.4eV and high bond strength, granting it intrinsic resistance to displacement damage and ionizing radiation. This capability allows GaN devices to operate reliably under the extreme thermal fluctuations and high-energy particle bombardment that are characteristic of the orbital environment. Research highlights that this resilience allows GaN to maintain stable carrier mobility and low-leakage currents, even when subjected to the extreme temperature cycles inherent to LEO missions, ensuring consistent signal integrity without heavy thermal shielding.^[4]

While GaN RF power amplifiers handle transmission, the sophisticated digital logic—including field-programmable gate arrays (FPGAs) and application-specific integrated circuits (ASICs)—controlling these systems requires precise, clean, and radiation-hardened power. In the “New Space” paradigm, components must balance cost-effectiveness with radiation tolerance. As a result, the industry is moving towards plastic-packaged, radiation-hardened-by-design solutions that meet the typical three- to five-year lifespan requirements of LEO missions.

The Newest Products for Your Newest Designs^®

To support the high power demands of LEO satellite electronics, STMicroelectronics has introduced the STEVAL-LEOPOL1V1 evaluation board (Figure 1). This board is designed to evaluate the LEOPOL1, a radiation-hardened 5A monolithic synchronous step-down regulator. The STEVAL-LEOPOL1V1 and LEOPOL1 chip are designed for LEO altitudes, offering a total ionizing dose (TID) immunity of 50 krad(Si). Additionally, the LEOPOL1 is single-event latch-up (SEL)-free up to 62MeV.cm²/mg, ensuring reliability against cosmic rays.

Figure 1: The STMicroelectronics STEVAL-LEOPOL1V1 evaluation board was developed and optimized for a typical LEOPOL1 application. (Source: Mouser Electronics)

The STEVAL-LEOPOL1V1 creates a compact, efficient power supply solution optimized for the harsh conditions of space. The board features a specific design to evaluate the LEOPOL1 regulator, which converts input voltages from 3V to 12V down to a regulated output. This feature makes it ideal for powering the FPGAs, microcontrollers, and ASICs that manage satellite RF communications and data processing. The board also utilizes a PowerSO-36 package, aligning with the “New Space” requirement for cost-effective components that deliver space-grade performance.

Tuesday’s Takeaway

As LEO constellations reshape vertical industries from agriculture to energy by providing global 5G coverage, the hardware orbiting above us must be as resilient as it is powerful. The synergy between GaN-based RF systems and robust power management empowers LEO constellations to maintain the vital 5G and 6G links the modern world depends on.

Sources

[1] https://ctu.ieee.org/
[2] https://doi.org/10.1109/MCOM.001.2001081
[3] https://doi.org/10.3390/mi16121421
[4] https://doi.org/10.3390/mi16121421

Emerging Battery Testing Approaches: A New Era of Diagnostics

Fri, 16 Jan 2026 23:11:50 GMT

(Source: Steveandfriend /stock.adobe.com; generated with AI)

As the world becomes increasingly electrified—from smartphones to electric vehicles (EVs)—the demand for high-performance, long-lasting, and safe batteries has never been greater. Lithium-ion batteries, although powerful and widely used in high-tech consumer applications, are prone to issues such as current leakage, dendrite formation, and thermal runaway. Each of these issues can cause catastrophic failure. To address these risks, engineers and researchers are developing new testing approaches that probe deeper into battery behavior, uncovering microscopic degradation mechanisms and offering real-time insights into battery health. In this blog, we examine some of the new and emerging diagnostic tests for batteries being developed, highlighting the ways these approaches deliver advanced energy storage.

The Push for Safer, Smarter Batteries

If the lithium-ion (Li-ion) fires in the smartphone and EV space over the last few years have taught us anything, it is that there is a continued need to build more stringent and robust safety and testing practices. These incidents have underscored the importance of robust testing protocols that go beyond surface-level diagnostics. Emerging battery testing approaches include physical and simulation-based testing that can probe current dynamics and battery structures at much smaller levels to check that batteries are running optimally and safely, as well as to detect any microscopic issues before they develop into a major thermal event. These methods include graphene Hall sensors and electrochemical mass spectrometry (EC-MS), and they are utilized in quality control (QC), in-field diagnostics, and research and development (R&D), providing a more comprehensive understanding of battery behavior throughout its lifecycle.

Graphene Hall Sensors: Mapping Current with Precision

One of the most promising innovations in battery diagnostics is the graphene Hall sensor, which measures the magnetic field in batteries to determine the local current. In Hall-effect sensors, when the active sensing surface is placed into a magnetic field, the charge carriers in the material deflect, causing a potential difference across the material. This process generates a voltage in the material, and by measuring the deflection and generated voltage, the strength of the magnetic field can be determined. In graphene-based sensors, the Hall effect is amplified due to graphene’s exceptional electrical properties, allowing for precise measurement of localized currents and fast response times.

Because they are non-contact, non-destructive, and can monitor localized currents without affecting battery operation, graphene Hall sensors can be deployed in real time, even in operational environments like EVs. Using graphene Hall sensors, engineers can:

monitor charge and discharge cycles,
assess the state of charge (SOC) and state of health (SOH),
detect current spikes and leakage,
identify hotspots that could lead to thermal runaway, and
map current distribution across the battery.

Graphene Hall sensors are especially well-suited for monitoring and testing one of the biggest safety challenges of higher powered Li-ion batteries: thermal runaway. Thermal runaway is a rapid increase in temperature that results from a defect. These rapidly spiking temperatures propagate through the cell and the battery pack, leading to fires and potentially an explosion. Graphene Hall sensors can be used as a battery monitoring tool to map currents and defects before they become serious thermal events. In this way, graphene Hall sensors can act as an early warning system for thermal runaway and other serious battery safety issues.

Electrochemical Mass Spectrometry

While graphene sensors focus on electrical behavior, electrochemical mass spectrometry (EC-MS) offers a window into the chemical processes occurring inside batteries. One current example of this diagnostic approach is Spectro Inlets, a Danish company pioneering the use of EC-MS to study gas evolution in Li-ion cells,^[1] which is a key indicator of degradation.

Traditionally, analyzing gas emissions requires complex setups in controlled environments. EC-MS simplifies this by using microfabricated membranes that interface directly with the battery cell, allowing gases to diffuse naturally into the spectrometer without the need for additional carrier gases or electrolyte loss. This technique enables researchers to identify specific degradation pathways, measure gas production rates over time, and predict real-world battery life spans more accurately than simulations alone.

EC-MS is particularly valuable in R&D, where understanding the root causes of battery aging can lead to more durable designs. Although currently used on a small scale, the technology has attracted attention from organizations like the Faraday Institution, signaling its potential for broader adoption.

Physics-based Simulations’ Role in Battery Testing

While physical testing is essential, physics-based simulation approaches are becoming equally vital in battery development. Simulations are important during the development of batteries to show how they should theoretically perform across several given scenarios. Physics-based models have gained popularity for battery monitoring and diagnostics. Recently, physics-based simulation models specifically geared toward batteries have emerged that more accurately predict the internal properties and degradation of batteries over time.

One standout platform is Python Battery Mathematical Modelling (PyBaMM), an open-source tool that enables engineers to simulate degradation mechanisms, performance metrics, and lifetime predictions based on fundamental physics.^[2] With thousands of engineers already using PyBaMM worldwide, it’s becoming a cornerstone of battery R&D. The platform allows for:

detailed analysis of degradation scenarios,
optimization of battery design and materials, and
integration with experimental data for hybrid testing approaches

Conclusion

Battery testing is entering a new phase—one defined by precision, sensitivity, and predictive capability. Whether it’s detecting microscopic faults before they become hazards or simulating complex degradation pathways, the tools now available are reshaping how we understand and manage battery performance.

As power demands grow and safety standards tighten, these emerging diagnostic methods will play a pivotal role in ensuring that batteries are not only powerful but also reliable and safe. The combination of physical and simulation-based testing will be the key to unlocking the full potential of energy storage technologies in the years to come.

[1] https://www.faraday.ac.uk/success-stories/spectro-inlets/
[2] https://pybamm.org/

New Tech Tuesdays: mMIMO Proves Crucial to 5G

Tue, 08 Oct 2024 05:01:00 GMT

New Tech Tuesdays

Join Rudy Ramos for a weekly look at all things interesting, new, and noteworthy for design engineers.

The telecommunications industry is constantly evolving, with each new generation bringing faster speeds, lower latency, and increased capacity. The latest iteration, 5G, is revolutionizing the way we live, work, and connect. In this week’s New Tech Tuesday, we see just how antenna technology is stepping up to meet the needs of modern communication.

The Key to 5G

At the heart of the 5G revolution lies massive multiple-input, multiple-output (mMIMO) technology, a key enabler of 5G's enhanced capabilities. As an advanced antenna technology, mMIMO significantly improves the performance and efficiency of wireless communication systems. mMIMO employs a large number of antennas at the base stations to simultaneously send and receive data to multiple users at once, using the same frequency, thereby increasing the capacity and reliability of the network.

mMIMO’s ability to improve coverage is essential for supporting data-heavy applications and for the evolution of 5G and beyond. By addressing the fundamental challenges of increasing capacity, enhancing data rates, and reducing latency, mMIMO proves crucial for supporting technologies such as the Internet of Things (IoT), autonomous vehicles (AVs), and augmented reality (AR).

With mMIMO serving such a fundamental role in the advancement of 5G communications and beyond, it’s important to know some key mMIMO terms:

Spatial Multiplexing: Sending multiple data streams on the same frequency but separated in space, like focused beams.
Latency: The delay between sending a request and receiving a response, for example, lag in a video call.
Data throughput: The amount of data that can be sent over a connection in a given amount of time.
Spectral Efficiency: A measure of how efficiently a communication system uses the radio frequency spectrum.

As networks evolve beyond 5G, mMIMO continues to be a cornerstone for developing more efficient and capable wireless communication systems. However, to fully realize the potential of mMIMO, high-performance RF components are essential.

The Newest Products for Your Newest Designs^®

This week’s New Tech Tuesday features the QPA9822 mMIMO pre-driver from Qorvo. The QPA9822 (Figure 1) is a linear 5G high-gain, high-drive amplifier designed to address the demanding requirements of mMIMO systems.

Figure 1: The QPA9822’s 16-pin 3mm × 3mm SMT package offers a space-saving solution for integration into dense mMIMO antenna arrays. (Source: Mouser Electronics)

The QPA9822 is a driver amplifier specifically designed for 32-node mMIMO systems that enable wideband 5G New Radio (NR) instantaneous signal bandwidths of up to 530MHz. It is ideally suited for critical 5G deployment and other mMIMO applications. This true powerhouse for 5G mMIMO delivers an impressive 39dB gain at 3.5GHz and a peak power of +29dBm, achieving a P1dB of 28dBm. This exceptional gain ensures robust signal amplification, extending coverage and improving signal quality in mMIMO deployments.

Operating within the 3300–4200MHz range, the QPA9822 is designed to handle the wideband 5G NR instantaneous signal bandwidths required for high-speed data transmission.

The exceptional performance characteristics of the QPA9822 make it a versatile component suitable for various wireless applications and industries, including defense, SATCOM, and small cells. The QPA9822 is engineered to meet the stringent demands of 5G mMIMO, particularly in the N77 band, which is crucial for global 5G deployment. Its high gain and linearity, coupled with its ability to handle wide bandwidths, make it a key enabler of high-speed, high-capacity 5G networks.

Tuesday’s Takeaway

Qorvo's QPA9822 exemplifies the company's dedication to leading 5G technology advancements in cellular infrastructure and RF innovation. This driver amplifier’s impressive specifications and compatibility features make it an optimal choice for 5G infrastructure applications, playing a crucial role in shaping the future of wireless communication.

Sources:

Chataut, Robin, and Robert Akl. “Massive MIMO Systems for 5G and beyond Networks—Overview, Recent Trends, Challenges, and Future Research Direction,” Sensors 20, no. 10 (January 2020): 2753. https://doi.org/10.3390/s20102753.
Khan, Muhammad Farhan, and Dirk Pesch. “On Performance of Multi-User Massive MIMO for 5G and Beyond,” In 2022 IEEE 95th Vehicular Technology Conference: (VTC2022-Spring). https://doi.org/10.1109/VTC2022-Spring54318.2022.9860567.
“Massive MIMO Evolution Towards 2025 and Beyond (MM+),” IEEE Communications Society. https://www.comsoc.org/education-training/media-center/massive-mimo-evolution-towards-2025-and-beyond-mm.

New Tech Tuesdays: Challenges to Public EV Charging Infrastructure

Tue, 24 Sep 2024 05:01:00 GMT

New Tech Tuesdays

Join Rudy Ramos for a weekly look at all things interesting, new, and noteworthy for design engineers.

While electric vehicles (EVs) are becoming more ubiquitous, there are several issues EV owners encounter when looking to recharge and get back on the road. A significant problem with public EV charging stations is the lack of etiquette among some EV drivers. Referred to as “charger hogs,” these individuals remain connected to a charging station for extended periods, even when their batteries are nearly full.

In this week’s New Tech Tuesday, we look into this and other challenges facing public EV charging infrastructure.

Not Always a Lack of Charging Etiquette

Charging practices for EVs can sometimes be misunderstood as poor etiquette rather than a matter of efficiency. For instance, while charging profiles for devices like smartphones and laptops (e.g., power delivery, quick charge) are designed to protect battery health by regulating power and extending battery life, EV charging protocols also focus on optimizing power transfer. EV chargers use standards such as the Open Charge Point Interface (OCPI) and other proprietary standards that are tailored to EV needs, which can vary somewhat widely.^[1] The aggregated data in Table 1, gathered from a variety of sources, shows the main types of EV chargers, detailing both proprietary (Figure 1) and non-proprietary variants, along with relevant information on their usage and compatibility.

Table 1: Types of chargers typically found at EV charging stations. (Source: Author)

Official Name	Charging Level	Kilowatt Rating (kW)	Type of Connector	Region Most Likely Found	Automakers Using It	Proprietary Information
AC Level 1	Level 1	1.4kW to 1.9kW	Standard 120V (J1772)	North America, Europe	Most automakers (including Tesla with an adapter)	Non-proprietary; standard outlet, slowest charging
AC Level 2	Level 2	3.3kW to 19.2kW	J1772 (Type 1/Type 2)	North America (J1772), Europe (Type 2)	Most automakers (including Tesla with an adapter)	Non-proprietary; faster than Level 1, used in residential and public stations
DC Fast Charging	Level 3	50kW to 350kW	CCS (Combo)	North America, Europe	Most automakers (Ford, GM, BMW, VW, etc.)	Non-proprietary; high-speed charging standard in many regions
Tesla Supercharger	Level 3	72kW to 250kW	Tesla Connector (North America), CCS (Europe)	North America, Europe	Tesla	Proprietary in North America; adapters needed for non-Tesla vehicles
CHAdeMO	Level 3	50kW to 100kW	CHAdeMO	Japan, North America	Nissan, Mitsubishi	Proprietary; slowly being phased out in favor of CCS in some regions
GB/T	Level 3	50kW to 300kW	GB/T	China	Chinese automakers (BYD, NIO, etc.)	Proprietary; standard in China for domestic vehicles

The issue with public EV charging stations often arises from the deep-rooted habit of completely filling the gasoline tank on internal combustion engine (ICE) vehicles, a habit that does not translate to EVs. Many new EV owners might not realize that charging their battery beyond 80 percent significantly slows down the charging speed and will extend the time the charger is occupied. This can inconvenience others who need to use the charging station. Therefore, it is more about the efficiency of charging rather than intentional disregard for others.

Figure 1: This proprietary supercharger stall in Roseville, California, features a commemorative plaque to mark Tesla’s 50,000^th supercharger installation worldwide. (Source: GameSyns - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=137842733)

Scarcity of Chargers

Another major challenge is the limited availability of public chargers, particularly fast chargers. This shortage can lead to anxiety among drivers about finding a charging station, causing them to stay plugged in longer than necessary. The situation is worsened by the increasing number of EVs on the road, despite a slowdown in EV sales growth.^[2] The insufficient number of chargers can deter potential buyers from choosing EVs.

As of 2024, California has approximately 25 percent of all the charging stations in the US with over 14,000, while states like Alaska and much of the upper Midwest each have 100 or fewer stations.^[3] For EV owners living in or traveling through these expansive areas, it’s often advisable to fully charge their vehicles whenever possible, even if it takes longer.

The Newest Products for Your Newest Designs^®

This week's New Tech Tuesday features electrification solutions from Infineon Technologies that aim to expedite the EV charging experience.

Infineon Technologies' EasyPACK^™ 2B IGBT Power Modules are designed to deliver high efficiency and reliability in power conversion applications like fast EV charging stations. The modules utilize insulated-gate bipolar transistor (IGBT) technology, which ensures minimal conduction and switching losses during the power conversion process, which is critical for fast EV charging where efficient energy transfer is essential. Their modularity supports different power levels for adapting to different charging speeds and is equipped with advanced thermal management for safe operation under high power and continuous load conditions.

Tuesday’s Takeaway

The challenges facing public EV charging infrastructure are multi-faceted, encompassing issues from charging etiquette to the scarcity and availability of fast chargers. These obstacles often stem from ingrained habits of drivers accustomed to traditional gasoline refueling and the rapid rise in EV adoption. Although companies are making strides in expanding infrastructure and introducing new technologies like advanced power modules and MOSFETs to improve charging efficiency, there remains a need for continued innovation and strategic solutions such as idle fees and dynamic pricing. Only by overcoming these challenges can the EV market realize its full potential, ensuring a seamless and efficient charging experience for all users.

Sources:

[1] https://afdc.energy.gov/fuels/electricity-stations
[2] https://www.goodcarbadcar.net/
[3] https://www.cnet.com/home/electric-vehicles/how-many-ev-charging-stations-are-there-in-the-us/

New Tech Tuesdays: Energy on the Go: The Evolution of Portable Power Banks

Tue, 07 Nov 2023 06:01:00 GMT

New Tech Tuesdays

Join Rudy Ramos for a weekly look at all things interesting, new, and noteworthy for design engineers.

In today's world of ubiquitous mobile devices, a low-battery notification can often feel like the digital equivalent of running out of gas on a deserted highway. Thankfully, portable power banks have come to the rescue, ensuring our devices stay powered when we need them the most.

Full disclosure: I wasn't immediately sold on portable power banks. In their early days, they seemed limited, catering to specific devices, limited in port offerings, or lacking the capacity to charge multiple gadgets simultaneously. Furthermore, their charging speeds were often underwhelming, with the units requiring several hours for a full recharge. Plus, the challenge of compatibility with varying power delivery standards was daunting. However, with advancements in technology, today's portable power banks have addressed these concerns, transforming them into indispensable tech marvels.

Compact Convenient Mobile Power

But what exactly has contributed to the impressive rise and excellent performance of these compact energy reservoirs? I believe it’s the result of a perfect storm: the fusion of advanced battery technologies, groundbreaking Gallium Nitride (GaN) chargers, efficient power delivery (PD) designs, and the widespread acceptance of USB-C^™, all supported by economies of scale.

Take, for example, the Anker 737 PowerCore 24K Series 7 power bank, which I recently purchased (Figure 1). This 630g portable power bank is Power Delivery (PD3.1) and Quick Charge compliant and features six 4,000 milliampere-hours (mAh) lithium-ion (Li-Ion) cells for a 24,000mAh power bank capacity, equivalent to 86.4 watt-hours (Wh), which puts it nicely below the 100-watt FAA allowable limit for air travel.

Formula for converting a battery’s capacity from mAh to Wh: (mAh) x (V)/1000 = (Wh). For example, if you have a 4,000mAh battery rated at 21.6V,

the power is 4,000mAh x 21.6V / 1000 = 86.4Wh.

Thanks to GaN, the Anker 737 power bank features 140W high-speed output discharge capabilities. This power bank is designed for optimal convenience and speedy performance in a sleek, compact design. It boasts real-time temperature monitoring and universal device compatibility to ensure your mobile gadgets stay powered without a hitch. With robust charging capacities through two USB-C ports (140W maximum output each) and one USB-A port (18W maximum output), it can simultaneously energize three devices or enable pass-through charging for two devices while replenishing its own battery. Simply plug your cell phone, laptop, camera, or other gadgets into the power bank and connect it to the power source. This power bank outshines even the latest cell phones in recharge speed, boasting a formidable 140W recharging capability that soars from 0% to 100% in under an hour, storing more than 4X the charging potential of the latest flagship cell phones.

Figure 1: The Anker’s 737 140W output can charge power-hungry devices like a MacBook Pro 16-inch as effortlessly as charging a smartphone or earbuds. (Source: Author)

Powering the Future

Li-Ion Batteries: The Heart of the Power Bank

At the heart of every power bank lies its battery technology. Li-Ion batteries have become the industry standard due to their high energy density, long cycle life, and decreasing costs. They pack a lot of power in a small space, making them ideal for portable applications. As technology and manufacturing processes have improved, the cost of producing these batteries has reduced significantly, making high-capacity power banks more affordable for the masses.

GaN Power Chargers: A Revolutionary Shift

Gallium Nitride (GaN) chargers have transformed the way we think about charging speeds. GaN is a next-generation semiconductor material that offers greater efficiency and can handle higher voltages than traditional silicon chargers. This translates to faster charging times and compact charger designs, ensuring your power bank recharges rapidly and is ready to go when you are.

Fast PD and USB-C: Universal Charging at Lightning Speeds

Fast Power Delivery (PD) is a game changer, allowing devices to charge at optimized speeds safely. Combined with the pervasiveness of the USB-C port—now found on most modern smartphones, tablets, and laptops—users can enjoy a standardized, high-speed charging experience across multiple devices. This simplifies the charging ecosystem, ensuring that one power bank can serve a variety of electronic needs.

Economies of Scale: Delivering Affordability to the Masses

As demand for power banks has surged, large-scale manufacturing processes have evolved to meet the demand, resulting in economies of scale. This has made it feasible for companies to produce high-quality power banks at truly competitive prices, making them accessible to a larger segment of the population.

Safety First: The Role of the BMS

With great power comes great responsibility. The increased energy densities of Li-Ion batteries come with risks, such as thermal runaway—a chain reaction within the battery that can lead to overheating and potential explosions. The Battery Management System (BMS) is an unsung hero in this narrative. It monitors and controls the charge and discharge of the battery, ensuring it operates within safe parameters. The BMS also manages the battery's temperature, protecting it from potential hazards and ensuring longevity.

Featured Products

Given the inherent risks of Li-Ion batteries, organizations like the FAA have taken note. To ensure the safety of air travel, the FAA has imposed limits on the transport of spare (uninstalled) Li-Ion and lithium metal batteries, including power banks. Li-Ion rechargeable batteries are limited to a rating of 100 Wh per battery. These limits allow for nearly all types of Li-Ion batteries to be used by the average person in their electronic devices.

This week’s New Tech Tuesday features two key devices that help keep Li-Ion power banks safe for air travel.

The Texas Instruments BQ25756 is a versatile bidirectional buck-boost battery charge controller tailored for Li-Ion, Li-polymer, and LiFePO4 chemistries, spanning a vast 4.2V-70V input voltage and up to 70V battery voltage. Its standout features include 1-14 cell Li-Ion and 1-16 cell LiFePO4 support, a synchronous buck-boost controller with adjustable frequencies from 200kHz to 600kHz, and an integrated loop compensation with soft start. With bidirectional power support, the device efficiently manages charging, ensuring ±0.5% charge voltage accuracy and ±3% precision for both charge and input current regulations. Furthermore, its reverse mode aligns with the USB-PD EPR power profile, offering adjustable voltage (3.3V-65V) and current (400mA-20A) regulations. Designers will appreciate the ease of I²C control with resistor-programmable options, bolstered by a 16-bit ADC for comprehensive monitoring. Ensuring device and battery safety, it integrates overvoltage, overcurrent, battery short, and thermal shutdown protections. Informative status indicators provide real-time feedback, all packaged compactly in a 36-pin 5mm x 6mm QFN.

Next, Vishay / BC Components' AEC-Q200-Qualified NTC SMD Chip Thermistors are designed for precision, offering a wide temperature range of -55°C to +150°C. As negative temperature coefficient (NTC) thermistors, they excel in temperature compensation, sensing, and protection across diverse sectors, from automotive to consumer electronics. The NTCS series stands out for its robust construction and reliability in thermal cycling environments, suitable for both PCBs and flexible circuits. These thermistors utilize bulk ceramic technology and are available in standard surface-mount sizes: 0402, 0603, and 0805. They boast a high sensitivity, resistance values at 25°C from 1KΩ to 680KΩ, and beta values ranging from 3370K to 4125K. Moreover, they are RoHS compliant, cULus recognized, and can seamlessly integrate into high-volume, automated manufacturing processes. Key applications include battery management, automotive systems, consumer electronics, and medical devices.

Tuesday’s Takeaway

In an era dominated by mobile devices, portable power banks have emerged as essential tools to prevent our gadgets from running out of power. Despite initial limitations, advancements in battery technology, the integration of Gallium Nitride chargers, and the adoption of universal USB-C have significantly improved their functionality and efficiency. Furthermore, economies of scale have made these tech wonders affordable for many. Technologies like the Texas Instruments BQ25756 and Vishay / BC Components' NTC SMD Chip Thermistors further enhance battery safety and efficiency. Ultimately, today's power banks are a testament to technological progress, ensuring our devices are always powered and ready to match the pace of our fast-moving world.

Sources:

“Portable Power Bank Market Report Overview.” Business Research Insights, October 16, 2023. https://www.businessresearchinsights.com/market-reports/portable-power-bank-market-103127.

New Tech Tuesdays: Nickel-Hydrogen Batteries: A Legacy of NASA’s Space Missions Shaping Modern Energy Solutions

Tue, 12 Sep 2023 05:01:00 GMT

New Tech Tuesdays

Join Rudy Ramos for a weekly look at all things interesting, new, and noteworthy for design engineers.

Since the 1960s, NASA has relied on an old yet dependable technology for powering the International Space Station (ISS), satellites, and other space vehicles: nickel-hydrogen (Ni-H₂) batteries (NHBs). These batteries are revered for their durability, long lifespan, and outstanding safety record, even under the most extreme conditions. Let's explore how these batteries function and their potential benefits for modern applications.

Tests conducted on these batteries often involve harsh treatment, such as deliberate perforation using nails or firearms. The results consistently prove the remarkable resilience of NHBs, as there's no explosion, fire, or material ejection—even in cases of hypervelocity impact. The surface temperature remains at a manageable 44 degrees Celsius (112 degrees Fahrenheit) and the pressure and voltage rapidly dissipate, preventing any catastrophic rupture.

Unlike common lithium-ion batteries, NHBs do not develop dendrites, which are tiny metal structures that build upon anodes during charging and can cause short circuits or other failures. This means the batteries can go through approximately 30,000 cycles—or around 30 years of daily use—without compromising their integrity, making them a low-maintenance solution for long-term energy storage.

The battery's chemical makeup is mainly hydrogen and water, meaning they're also environmentally friendly. Additionally, their manufacturing process is straightforward and uses abundant elements, nickel, and hydrogen, thus easing supply chain and cost issues.

Old Tech is New Again

So why is this legacy battery design now relevant again? And why have NHBs and their potential applications been overlooked until now?

Well, despite a 250 percent surge in nickel prices in 2022, the low-maintenance nature and longevity of these batteries potentially save substantial operational costs, particularly for renewable energy storage facilities. Also, when the time comes for disposal, these batteries are almost 100 percent recyclable. But the real reason these legacy batteries have been dormant is cost. Sky high cost!

But that all might soon change. EnerVenue, a California-based company specializing in energy storage solutions, has embarked on a large grid-scale gigawatt storage facility that will be located in Kentucky and will seek to capitalize on all the potential upsides of using NHBs.

EnerVenue feels that, like the proven technology used by NASA for more than 30 years, their Energy Storage Vessels™ (ESVs) feature an exceptionally long lifespan, eliminating the need for augmentation or oversizing. ESVs can be easily mounted in racks, containers, or stacked in custom warehousing. Their unique chemistry eliminates the need for preventative fire suppression. They can also reliably operate in a wide ambient temperature range without supplementary HVAC. ESVs dramatically reduce operating expenses and feature a much lower cost-per-cycle compared to lithium-ion chemistries.

3/30/30,000: Energy Storage Vessels can cycle up to 3 times per day without rest and boast an expected lifetime of 30 years / 30,000 cycles – enabling unique applications and business models for developers, integrators, and owners. - EnerVenue

The company is addressing the astronomical cost problem primarily by utilizing economies of scale and mass production of their ESVs. These batteries are still pricey, but EnerVenue’s large "gigafactory"—and potential future ones like it—will make them more affordable by eliminating the need for custom designs. By the end of 2023, EnerVenue expects the gigafactory to begin production.

Featured Products

Irrespective of the specific battery design, converting potential energy into electrical energy necessitates the implementation of a resilient and high-efficiency Battery Management System (BMS). This week's New Tech Tuesday highlights the introduction of BMS solution devices by Vishay / Dale and Nexperia.

The HV Intelligent Battery Shunt HV-IBSS-USB from Vishay / Dale is a reference design made to easily evaluate the low Temperature Coefficient of Resistance (TCR) of shunt WSBE8518. It uses a single USB-C connector to provide power to the circuit and to emulate a serial interface so engineers can conveniently make voltage, current, and temperature readings.

Due to the low TCR of the WSBE8518 (maximum ± 10ppm/K for 100μΩ) alongside the choice of low thermal drift components in the analog frontend, this reference design can achieve an overall TCR of approximately 44ppm/K max. without thermal compensation over the whole temperature range. The device is factory calibrated (values stored in onboard EEprom) to allow for current measurements with 0.2 percent and thermal drift for currents in the range of ±500A.

The TCR is a crucial parameter in current sensing measurements, especially in applications like BMS that involve monitoring and managing current flow in various components, including battery shunts. TCR indicates how a material's electrical resistance changes with changes in temperature. It's expressed as a fractional change in resistance per degree Celsius change in temperature (ΔR/R0 per °C), usually in parts per million per degree Celsius (ppm/°C).

In BMS, TCR plays a significant role for several reasons, including the precise measurement of current flowing into and out of the battery, as well as throughout the battery system. This is essential for monitoring the state of charge (SoC) and state of health (SoH) of the battery. TCR helps compensate for changes in resistance due to temperature variations, allowing for more accurate and consistent current measurements. Additionally, accurate current measurements enable the BMS to detect anomalies and potentially hazardous conditions like overcurrent situations, which can lead to thermal runaway or other safety risks. By compensating for temperature effects, the BMS can respond appropriately to changes in current flow, enhancing the overall safety and efficiency of the battery system.

Nexperia eMode GaN FETs offer a voltage range of 100V to 650V and superior ultra-high frequency switching performance. These general-purpose enhancement mode (eMode) Gallium Nitride Field-Effect Transistors (GaN FETs) deliver fast transition and switching capability with minimal conduction and switching losses.

Enhancement mode FETs are "normally-off," meaning that by default, the transistor is in an "off" state until a specific voltage to its gate terminal is applied, activating the transistor and letting current flow. This type of GaN FET is commonly used in power electronics because it's safer and more predictable—if there's no voltage applied, it stays off, reducing the risk of accidental current flow.

These power FETS are available in a DFN 8mm x 8mm surface mount package. Applications include high power density and high-efficiency power conversion, AC-to-DC and DC-to-DC converters, fast battery charging, and motor drives. For 650V and ≤ 150V industrial and consumer applications, Nexperia e-Mode GaN FETs provide the balance between switching performance and robustness.

Tuesday’s Takeaway

Nickel-hydrogen batteries, despite being old technology, continue to prove their worth, especially in the renewable energy sector. Although their initial cost is high due to the use of expensive metals, advancements in mass production and the potential for cost-saving through their durability and longevity make them an attractive option as energy storage vessels for companies like EnerVenue. As we gear towards more sustainable energy solutions, it's crucial to revisit and optimize tried-and-true technologies like NHBs, which have been quietly powering our space missions for decades.

In the realm of battery management, Vishay / Dale and Nexperia present solutions like the HV Intelligent Battery Shunt, which leverages TCR technology for current sensing measurements to ensure accurate current monitoring while enhancing battery safety and efficiency. Nexperia’s eMode GaN FETs represent a safer and more predictable option in high-power density electronics, designed to remain off until activated, thereby reducing the risk of unintended current flow. These FETs offer efficient power conversion in various applications, showcasing a balance between switching performance and robustness.

Innovation continues to merge lessons from NASA's legacy technology with modern applications, providing solutions that bridge the gap between reliability, sustainability, and efficiency in energy storage and management.

Sources

1. “EnerVenue Launches the Next Generation of its Energy Storage Vessels™ (ESVs).” EnerVenue. September 6, 2023. https://enervenue.com/enervenue-launches-the-next-generation-of-its-energy-storage-vessels-esvs/.
2. “EnerVenue Opening Gigafactory in Shelby County, Kentucky to Scale Production of its Differentiated Energy Storage Solutions.” EnerVenue. March 28, 2023. https://enervenue.com/enervenue-opening-gigafactory-in-shelby-county-kentucky-to-scale-production-of-its-differentiated-energy-storage-solutions/
3. Frate, David T., and Henry K. Nahra. “Hypervelocity Impact Testing of Nickel Hydrogen Battery Cells.” NASA Technical Reports Server, September 1, 1996, https://ntrs.nasa.gov/citations/19970001594.
4. van Halm, Isabeau. 2023. “The nickel price rollercoaster of 2022.” Mining Technology. January 10, 2023. https://www.mining-technology.com/features/nickel-price-surge-2022-markets/.

Why SiC Is Ideal for Green Energy

Fri, 12 May 2023 16:22:45 GMT

Why Silicon Carbide Is the Ideal Material for Green Energy Power Inverters

(Source: ImageOasis - stock.adobe.com)

Introduction

Green energy is essential in meeting exponentially-rising global energy demand while reducing emissions to curb global temperature rise below 1.5°C¹ in the coming decades. The criticality of this energy is driving the renewable energy market toward $2 trillion by 2030², with global energy storage systems (ESS) exceeding $13 billion itself³. And while the costs of green energy could come down by 35 percent for solar and nearly 50 percent for wind by 2030 thanks to the Inflation Reduction Act⁴, there are still challenges with creating a distributed infrastructure to convert renewable DC power to transmittable AC.

Inverters are the critical technology delivering this DC-AC conversion for green energy sources. And for a good reason: Inverters provide this conversion efficiency of up to 96 percent⁵. However, challenges exist with inverter technology in both their size and durability at scale despite their clear advantage in power conversion. In addition, the conventional architectures need active cooling and support of the heavy equipment.

To achieve technical performance and commercial success, engineers are converging on an ideal material for large-scale solar and wind inverters: silicon carbide.

Anatomy of a Renewable Energy Inverter

Renewable inverters require multiple specification values to ensure the desired performance. Among these are input [DC] current and voltage range, maximum AC power output, conversion efficiency target, and rated operating temperature range for an application.

Once design engineers have quantified these levels, they can design the green energy inverters comprised of building-block components:

DC intake (including disconnects and overload fuses): The DC intake component involves solar panels or wind turbines that connect renewable DC power to the inverter.
Power converter (including high-frequency transformer, MOSFETs/IGBTs, and control circuits): The power converter component converts the input DC power to AC output power.
AC output (including circuit breakers or fuses): The AC output component connects the inverter AC power to the application, such as a residence or commercial property.
Control system: The control system component involves monitoring and control devices for remote assessment, troubleshooting, and performance optimization.
Cooling system (including fans, heat sinks, or liquid cooling loops): The cooling system component involves active cooling to dissipate heat generated during inverter operation. This heat represents most of the inefficiency in power conversion and can damage device components.

Typical sizes for applications

Large-scale inverters will be necessary to meet the market demand described above. But inverter technology is not unique to the larger size; there are three primary levels for renewable power conversion:

Utility (central) inverter (>20kW): The utility inverter provides one inverter per set of solar panels, which reduces efficiency through diode loss.
Commercial (string) inverter (1-20kW): The commercial inverter provides a 1:1 inverter-to-panel ratio, connecting inverters in series to improve efficiency.
Micro-inverter (50-400W): The micro-inverter provides the highest efficiency through integrated inverter/MPP tracker within a solar panel.

Solutions for Power Discretes

Silicon has played a critical role in increasing the efficiency of photovoltaic (PV) cells. Currently, the material is also the incumbent solution for MOSFET and IGBT power semiconductors. However, with the exponential demand for renewable energy to reach 2050 decarbonization targets, the current inverter technology is reaching its limits.

Silicon limits the operating voltage, power densities, and temperatures of inverter performance. It also carries switching losses (reducing efficiency), which reduce the capacity of the inverter power supply. The lower efficiency requires a larger size to compensate, increasing the total cost of ownership and carbon footprint.

In contrast, silicon carbide (SiC) is a wide bandgap material that enables substantially higher-voltage operation, power densities, and temperatures. Along with reduced switching and conductive losses and lower-leakage currents than silicon, these advantages increase conversion efficiency. SiC saves 10MW/GW converted and 500W/s in operations for large-scale solar inverter applications, translating to direct energy savings⁶.

Wolfspeed Solutions

Wolfspeed is well-suited to provide SiC green energy inverter semiconductors, a growing market. With an estimated 60 percent market share and revenues projected to grow from $700 million in FY2022 to $1.5 billion in 2024⁷, the ceiling is very high for the market leader in a technology that comprises just 5 percent of the power semiconductor market at present.

Using a Wolfspeed Silicon Carbide MOSFET like the 1700V SiC Schottky Diode enables a lighter, smaller, and more efficient solar inverter. These advantages deliver fewer system losses, improve efficiency, and lower overall cost per watt compared with traditional silicon by reducing system part count.

In partnership with other renewable systems, solar power inverters and energy storage system (ESS)applications are updating grid power to improve resilience, meet high-current global energy requirements, and reduce their overall carbon footprint. These systems must be as energy and spatially-efficient as possible in rugged climates while remaining cost-effective.

Conclusion

Silicon was instrumental in improving the energy conversion efficiency of early PV panels and has been the incumbent power semiconductor material for over half a century. But with the increasing demands for renewable energy, particularly solar and wind, silicon is reaching its practical limit.

Silicon Carbide solutions address the needs and challenges of renewable energy systems containing semiconductors by delivering increased power density, reducing switching losses, and increasing switching frequency. Wolfspeed Silicon Carbide solutions enable more compact, lightweight, and efficient inverters for solar power semiconductors that convert sunlight to electricity in rugged environments with varying temperatures, high humidity, and other harsh conditions.

Author

Adam Kimmel has nearly 20 years as a practicing engineer, R&D manager, and engineering content writer. He creates white papers, website copy, case studies, and blog posts in vertical markets including automotive, industrial/manufacturing, technology, and electronics. Adam has degrees in chemical and mechanical engineering and is the founder and principal at ASK Consulting Solutions, LLC, an engineering and technology content writing firm.

Sources

1. “Special Report: Global Warming of 1.5oC.” ipcc. Accessed May 12, 2023. https://www.ipcc.ch/sr15/chapter/spm/.
2. “Renewable Energy Market Size Worldwide in 2021, with a Forecast for 2022 to 2030.” statista, January 27, 2023. https://www.statista.com/statistics/1094309/renewable-energy-market-size-global/.
3. “Top ‘Energy Storage Systems (ESS) Market’ Size 2023-2031, With 114 Pages.” MarketWatch. Accessed March 28, 2023. https://www.marketwatch.com/press-release/top-energy-storage-systems-ess-market-size-2023-2031-with-114-pages-2023-03-28.
4. How clean energy economics can benefit from the biggest climate law in US history, September 16, 2022. https://www.icf.com/insights/energy/clean-energy-economic-benefits-US-climate-law.
5. “The Efficiency of Solar Inverters.” SRNE. Accessed May 12, 2023. https://www.srnesolar.com/blog/the-efficiency-of-solar-inverters#:~:text=Solar%20inverters%20are%20very%20efficient,can%20be%20lost%20as%20heat.
6. “How Silicon Carbide Is Changing Solar Power Systems.” AltEnergyMag, May 28, 2020. https://www.altenergymag.com/article/2020/05/how-silicon-carbide-is-changing-solar-power-systems/33171.
7. Wolfspeed Leads The Pack Of Next-Generation Chipmakers, September 22, 2022. https://www.investors.com/research/the-new-america/wolfspeed-stock-leads-pack-of-power-chip-producers/.

Texas Instruments Wide Bandgap Solutions

Mon, 16 May 2022 20:30:42 GMT

(Source: Ivan Kmit – adobestock.com)

It All Started with a Calculator

When I was in high school and college, the ever-present tool I used as a fledging engineer was the Texas Instruments (TI) 30 calculator (Figure 1). The thing was indestructible. I used to demonstrate its toughness by letting it go from the third-story fire escapes onto the grass below, and it still worked. I used to throw them at school walls, and it never broke. Nothing I have ever bought has proven to be as excellent a value as this 5 x 8 keypad, a mathematical computational marvel. It was my introduction to Texas Instruments. And I was impressed. I wanted to work for them.

Figure 1: Vintage TI-30 calculator (Source: France1978/ CC BY-SA 2.0)

Along my engineering journey, I learned that TI is an expert in power management. Power management is an essential topic as electrification pushes designers to look for ever greater efficiency, and the high-voltage power market’s needs for higher power are growing. Texas Instruments believes that wide bandgap (WBG) technologies, such as gallium nitride (GaN), will play a key role in answering the demand for greater efficiency, performance, and reliability of high-voltage systems. TI is applying its expertise to innovate in the high-power space, focusing on highly integrated GaN solutions. TI’s integration approach is unique in the industry, enabling maximum performance, power density, ease of design, and lower system cost.

Why GaN

GaN ICs help maximize power density and efficiency. Using GaN devices can reduce power loss by 80 percent in power converters. The TI family of GaN FETs with integrated gate drivers and GaN power devices offers the most efficient GaN solution with lifetime reliability and cost advantages. GaN transistors switch much faster than silicon MOSFETs, which allows engineers to design higher frequency power stages with smaller magnetic components. Additionally, GaN provides power density improvement while offering the potential to achieve lower-switching losses.

Faster Switching Speed Than Discrete GaN FETs

TI's GaN FETs with integrated drivers can reach switching speeds of 150V/ns. These switching speeds, combined with a low-inductance package, reduce losses, enable clean switching and minimize ringing.

Smaller Magnetics, Higher Power Density

Enabled by faster switching speeds, TI's GaN devices can help you achieve switching frequencies over 500kHz, which results in up to 60 percent smaller magnetics, enhanced performance, and lower system cost.

Built for Reliability

TI's GaN devices are designed to keep high-voltage systems safe, thanks to a proprietary GaN-on-Si process, more than 40 million hours of reliability testing and protection features.

Designers use TI GaN ICs in many applications, from telecommunications, servers, motor drives, and laptop adapters to onboard chargers for electric vehicles.

TI GaN for Servers

Server racks are valued for their computational power per the required energy consumption and floor space (Figure 2). This means an ever-present need to increase the server’s power supply. Additionally, every watt (W) of heat output is a watt of cooling required by the server installation. One percent improvement in power efficiency improvement equates to approximately $70 of savings for every 1kW of power supply capability. GaN FETs also have lower switching losses when compared to traditional silicon (Si) FETs. Over the server’s lifetime, savings netted from higher efficiencies across a data center may equal millions of dollars.

Figure 2: Server racks maximize computational power, energy efficiency, and floor space. (Source: Michail - adobestock.com)

A wide range of industrial applications require weatherproof enclosures or have limited cooling capacities; as a result, they require expensive heatsinks to function properly. These applications are where the value of TI’s GaN solutions shines. They provide higher power densities in a smaller space at the same power level. Achieving more power in the same space is realized by GaN’s ability to switch at higher frequencies. This allows customers to shrink the size of server power supply units (PSUs) while reducing power losses—by approximately 30 percent to 40 percent—and energy consumption.

For Automotive

Vehicle electrification is transforming the automotive industry, and consumers are increasingly demanding vehicles that can charge faster and drive farther. As a result, engineers are being challenged to design compact, lightweight automotive systems without compromising vehicle performance. TI has automotive GaN FETs that enable the reduction in size of electric vehicle (EV) onboard chargers and DC/DC converters by as much as 50 percent compared to existing Si or SiC solutions. The result is allowing engineers to achieve extended battery range, increased system reliability and lower design cost.

Uniquely Integrated

Texas Instruments' specific approach to integrating the gate driver and other functionality with GaN field effect transistors (FETs) offers the simplest and best solution for GaN across the market. Integrating gate drivers with the GaN FETs improves performance. Many semiconductor manufacturers integrate the drivers, but only TI is unique in that, presently, they are also integrating biasing and safety features (Figure 3). This adds value to customers by helping to reduce parasitics between drivers and FETs. It simultaneously reduces loop inductance, which helps lead to faster switching speeds (>2x). Other integration features simplify the general design by handling power management and protection features.

Figure 3: Texas Instruments offers uniquely integrated gate drivers with GAN FETs. (Texas Instruments)

TI and Mouser GaN Together

Texas Instruments LMG34XX-BB-EVM GaN System Evaluation Board is a fully integrated solution that may get used for prototyping (Figure 4). This breakout board further simplifies the design process with GaN and makes it friendly for engineers. It may be employed to configure any LMG34xx half-bridge board, such as a synchronous buck converter. By providing a power stage, bias power, and logic circuitry, this evaluation module allows for quick measurements of the GaN device switching. This evaluation module can deliver suitable output current with appropriate thermal management (forced air, low-frequency operation, etc.) to ensure the maximum operating temperature does not get exceeded.

Figure 4: Texas Instruments LMG34XX-BB-EVM GaN System Evaluation Board (Mouser Electronics)

Conclusion

My TI-30 calculator was an integrated computational powerhouse for its era. Likewise, TI is also a leading innovator when it comes to GaN solutions that play a crucial role in answering the demand for greater efficiency, performance, and reliability of high-voltage systems. Looking for an integrated approach that is truly unique in the industry, enabling maximum performance, power density, ease of design, and lower system cost? Look to TI.

Author

Paul Golata joined Mouser Electronics in 2011. As a Senior Technology Specialist, Paul contributes to Mouser’s success through driving strategic leadership, tactical execution, and the overall product-line and marketing directions for advanced technology-related products. He provides design engineers with the latest information and trends in electrical engineering by delivering unique and valuable technical content that facilitates and enhances Mouser Electronics as the preferred distributor of choice.

Before joining Mouser Electronics, Paul served in various manufacturing, marketing, and sales-related roles for Hughes Aircraft Company, Melles Griot, Piper Jaffray, Balzers Optics, JDSU, and Arrow Electronics. He holds a BSEET from the DeVry Institute of Technology (Chicago, IL); an MBA from Pepperdine University (Malibu, CA); an MDiv w/BL from Southwestern Baptist Theological Seminary (Fort Worth, TX); and a PhD from Southwestern Baptist Theological Seminary (Fort Worth, TX).

How WBG Is a Step Toward Efficiency Being “1”

Tue, 10 May 2022 03:27:11 GMT

(Source: Littelfuse)

As a mountain bike enthusiast, I take calculated risks. For me to improve, I must push myself to jump over obstacles more quickly, increase my speed, and cut corners tighter while at the same time conserving energy for a strong finish. Though adventurous, I am far from being a daredevil attempting and succeeding in landing fantastic canyon jumps (Figure 1) like the skilled mountain bike riders in the Red Bull Rampage YouTube videos. At each stage of the race, my goal is to close the gap between my actual performance and my potential.

Figure 1: Cyclist jumping on a bicycle between two giant boulders. (Source: anatoliy_gleb - stock.adobe.com)

Like mountain biking, industrial applications are always better with increased efficiencies and power. One of the ways this gap is being jumped is by employing Wide Bandgap technology. Wide Bandgap technology is constantly improving, and more offerings are becoming available and more affordable than just a few years ago. This blog will discuss how Littelfuse Silicon Carbide (SiC) products are ideal for applications where improvements in efficiency, reliability, and thermal management are desired.

Littelfuse SiC MOSFETs

All Littelfuse SiC MOSFETs are optimized for high-frequency, high-efficiency applications (Figure 2). These SiC MOSFETs offer low gate charge, low output capacitance, and low gate resistance for high-frequency switching. These devices also feature low drain-source on-state resistance. These MOSFETs’ low gate charge and on-resistance translate into lower conduction and switching losses. Littelfuse offers in-house designed, developed, and manufactured SiC MOSFETs with low gate charge and output capacitance, industry-leading performance, and ruggedness at all temperatures. Littelfuse SiC MOSFETs come in a variety of packages, configurations, and voltage and current classes. Typical industrial applications that can benefit from using SiC-MOSFETs include motor drives, photovoltaic (PV) solar inverters, Uninterruptible Power Supply (UPS) systems, and modular multilevel converters.

Figure 2: Applications that benefit from SiC-MOSFETs due to increased efficiency include motor drives, PV solar inverters, UPS systems, and modular multilevel converters. (Source: romaset - stock.adobe.com)

Let’s look more closely at one specific example. It is a use case related to the low-cost design and high performance of a 60W auxiliary switched-mode power supply (SMPS). Using a 1700V-class device, such as SiC MOSFETs from Littelfuse, specifically their LSIC1MO170E0750 N-Channel SiC MOSFET offering (Figure 3), allowed the power supply to accept a wide range of input voltages from 300V to 1kV.

Figure 3: LSIC1MO170E0750 N-Channel SiC MOSFET offers low gate charge resistance and ultra-low on-resistance for high-frequency switching applications. (Source: Mouser Electronics)

Industrial Auxiliary Power Supply Design Considerations

A simple low complexity design with high reliability is required to ensure that the auxiliary supply does not become a limiting factor to system reliability. Single-switch flyback topology is the most common selection for low-power DC-DC power conversion due to its simple structure, lowest component count, and low cost. However, there are several challenges to selecting silicon MOSFETs for a single switch flyback topology for auxiliary power supply applications. In a flyback topology, the power switching device must have the voltage capability to withstand a total system voltage that addresses the highest input supply, transformer induced effects, secondary reflected voltage, and circuit arrangement/layout effects.

At 1000V input, the peak voltage on a power switching device can be easily over 1200V, making it challenging to select silicon (Si) MOSFETs with proper blocking voltages. A 1500V Si MOSFET will have a low margin and raise reliability concerns. Si MOSFETs rated 2000V and above can provide a sufficient margin. Still, the specific on-state resistance is much higher than lower voltage MOSFETs, reducing converter efficiency and compromising heat management. This consequence may necessitate more extensive cooling solutions even for a low power conversion application. In addition, the cost of >2000V rated Si MOSFETs is much higher. Two-switch flyback or other topologies should be employed to use Si MOSFETs rated 1500V and lower. However, the design complexity and converter component counts will increase significantly in a two-switch flyback topology.

Solution: 1700V_DS, 750mΩ SiC MOSFET

The introduction of 1700V SiC MOSFETs provides a possible solution by using a simple single-switch flyback topology for such applications to achieve a wide input voltage range. The 1700V breakdown voltage provides enough voltage margin even for 1000V input voltage. The specific on-resistance of a 1700V SiC MOSFETs is much lower than that of a 2000V-device and above rated Si MOSFETs.

Additionally, SiC MOSFETs have lower switching losses compared to Si MOSFETs. Lower switching losses also provide an option to increase the switching frequency of the auxiliary power supply to reduce transformer size and weight.

The TO-247 package it comes in also provides a large surface area and good thermal conductivity for simpler thermal management than smaller outline packages for low voltage devices.

WBG for Industrial Power Supply Solutions

With Littelfuse's Wide Bandgap SiC MOSFETs, designers can narrow the gap with a greater margin to achieve their power-supply and efficiency solutions. One thing is for certain. It is much easier to close this gap than to jump my bike across my next chasm.

Author

Maximizing Power Density in High Voltage Converters Using Wide Bandgap Technology

Fri, 03 Dec 2021 11:14:15 GMT

(Source: STMicroelectronics)

Increasing power density and shrinking power supplies are nothing new. This trend is projected to continue, enabling new markets, applications, and products. This blog introduces design engineers to how STMicroelectronics (ST) power solutions incorporate wide bandgap (WBG) technology to help drive the device miniaturization trend.

The Importance of Higher Power Density

Higher power density is vital to meeting the increasing energy demand everywhere and the ongoing market needs for smaller and more efficient power supplies. Semiconductor suppliers have managed to get a lot of utilization out of standard silicon-based devices, and silicon-based devices will continue to be a significant part of power systems. However, wide bandgap semiconductor materials have substantial advantages for achieving the most compact and efficient power solutions. Gallium Nitride (GaN), for example, is a powerful solution to address these challenges and advance power density and miniaturization capabilities. ST has used GaN technology in its innovative MasterGaN family of devices. MasterGaN can be applied to a resonant LLC converter to create a heatsink-less 250W power supply.

GaN

As a wide bandgap semiconductor, GaN power FETs feature greater power density and can work at higher voltages, operate at higher frequencies, and enable smaller devices. The critical phenomenon that differentiates GaN from traditional silicon (Si) semiconductor devices is its higher bandgap. The bandgap is the energy needed to excite an electron to have it jump from the top of the valence band to the bottom of the conduction band, where it can be used in the circuit. Increasing the bandgap has a significant impact on that device.

Materials like GaN that have a larger bandgap can withstand stronger electric fields. This robustness allows GaN to operate at higher voltages and higher electron mobility and saturation velocity. These key attributes make GaN switches ten times faster and significantly smaller at the same resistance and breakdown voltage as equivalent silicon components. GaN power FETs are sparking power engineering with their increased speed, efficiency, and power density that are way beyond the capabilities of traditional silicon MOSFETs. Market demand for greater efficiency and power density is pushing the adoption of GaN in compact, portable, and high-power applications. Powerful chargers are a key growth area for fast charging smartphones, tablets, and mobile applications. GaN has many other applications that would greatly benefit from its capabilities, such as EV charging, telecom, and high-power server applications.

Solving Design Challenges with MasterGaN

Discrete GaN transistors traditionally require dedicated high voltage half-bridge gate drivers that take up a significant amount of board space. The discrete approach also introduces additional inductance and capacitance on the highly sensitive GaN gates. MasterGaN solves these design challenges through the package-level integration of gate drivers with GaN transistors. ST’s MasterGaN product family combines high-voltage smart-power BCD-process gate drivers with high-voltage GaN transistors in a single package. The MasterGaN family has three key attributes: Compactness, Robustness, and Ease of Design. MasterGaN achieves compactness due to its high-power density; it is ¼ the size of a comparable silicon solution. The MasterGaN devices are robust and include an offline driver optimized for GaN High Electron Mobility Transistors (HEMT). The straightforward design is an innovative solution in a 9mm x 9mm quad flat no-lead (QFN) package that can reduce system size by up to 70 percent, enabling chargers and adapters to be up to 80 percent lighter.

By leveraging the high level of integration of MasterGaN, it is possible to create a 250W compact, highly efficient switch mode power supply without heatsinks (Figure 1). The power supply offers an excellent example of reducing space on a power supply design. The board is architected as a mainboard with two vertical daughter cards. The daughter card on the left is the MASTERGAN1 circuit, while the one on the right is the synchronous rectifier circuit for the secondary side. The design includes short circuit, overload, brownout, and overvoltage protection. The ST L6599A resonant LLC controller in this design runs at a frequency of 160kHz, although the controller can run up to 700kHz, and the design features integrated gate drivers with a 15V output drive. MasterGaN is entirely compatible with the L6599A due to its wide input-voltage range and high-frequency capability. This design also includes an SRK2001 LLC resonant controller. When combined with standard silicon MOSFETs, this controller helps maximize power-supply efficiency by reducing output losses.

Figure 1: MASTERGAN1 implementation into resonant LLC converter (Source: STMicroelectronics)

When designing with high-performance switched-mode power supplies, designers must exercise care to ensure all power supply pins are correctly fed and decoupled. Designers also need to make sure control signals are correctly configured to extract the full benefits of GaN.

Thermal management is also essential, and ST has some tips to optimize board layout to keep things running cool. MasterGAN features three sets of supply pins: a front-end supply (VCC), a floating high-side supply (BOOT), and a low-side (PVCC) supply. Note that both low- and high-side drivers are floating. Combined with the integrated level shifters, these floating supplies help ensure proper gate drive by making the input signals insensitive to the inductive noise coupling that would result if the two grounds were connected. These three supplies can all be powered independently, although, in many applications, the high-side driver can be supplied by VCC through the integrated Bootstrap Diode. This bootstrap structure is turned on during low-side ON time only. This structure reduces the component count in medium frequency (up to typically 400kHz) applications. As the switching speed increases, consider powering through an external higher performance bootstrap diode. Supply source basics are shown in (Figure 2).

Figure 2: Supply Sources Basics (Source: STMicroelectronics)

MasterGaN input logic was explicitly designed to make driving GaN transistors as straightforward as possible. For MasterGaN, the upper voltage limit of the input pins is 20V regardless of the VCC value. This feature makes it easy to use MasterGaN with a “MOS-oriented” controller that operates at a typical VCC of 12V or more, as in the L6599A in the design example. The thresholds also allow MasterGaN to be connected to a microcontroller with 3.3V logic for implementing your own custom SMPS algorithm. There’s not much more to it when connecting the control signals to MasterGaN than making sure they are connected! One could add a low-pass filter to the signal path to eliminate the risk of accidental switching if the system is noisy. MasterGaN devices internally buffer logic inputs (LIN, HIN, and SD/OD) with Schmitt triggers with an accurate turn-on/turn-off threshold to improve noise immunity and increase the repeatability of the propagation delays. Internal pulldown resistors in the MasterGaN devices avoid undefined voltage levels when logic inputs are high impedance.

Thermal Management in Power-Supply Design

Thermal management is among the most critical aspects of power-supply design and board layout. The 9mm x 9mm dual-flat no-leads (DFN) package features three exposed pads that must be soldered to the circuit board. Thermal resistance to the top case is much higher than to the exposed pads on the bottom. This design facilitates the removal of heat through the PCB and copper-pour areas (Figure 3).

Figure 3: Illustration of the board layout and thermal map showing the high-temperature areas. (Source: STMicroelectronics)

On the MasterGaN circuit, the current-carrying GAN transistors are beneath the large pads labeled SENSE and OUT. These are the heat-critical locations of the package. Pay close attention to maximizing heat extraction when laying out the board. OUT is connected to the high-side transistor source, while SENSE is connected to the low-side transistor source. In addition to the EVLMG1-250LLC LLC demo board here, ST has other evaluation platforms to help designers prototype, test, and develop high-performance power supplies. EVALMASTERGAN1 and 2 are available now, as well as the EVLMG1-250WLLC.

The EVLMG1-250WLLC evaluation board provides strong efficiency and thermal results. The results show a solid platform for developing and understanding the switching characteristics of MASTERGAN1 when integrated into an LLC resonant converter (Figure 4).

Figure 4: (a) Efficiency vs. Load of EVLMG1-250WLLC, (b) Thermal map. (Source: STMicroelectronics)

Conclusion

GaN technology is creating a new wave of power conversion approaches with greater power density and higher efficiency. ST uses GaN to develop cutting-edge products that help engineers design advanced power supplies more efficiently with our highly integrated MasterGaN family of GaN half-bridges with integrated gate drivers. Following a few good design guidelines can help designers maximize power density.

For more information, visit STMicroelectronics MASTERGAN GaN Half-Bridge High Voltage Drivers.

Infineon Technologies CoolSiC™ Works in the Trenches

Wed, 12 May 2021 21:06:00 GMT

(Source: Infineon Technologies)

The saying goes: “The battle is won in the trenches.” It means that people on the front line of the action determine the final winning outcome by their collective hard work and effort. In the following, we’ll review how design engineers involved in power-management applications operate “in the trenches” and what it takes for them to win.

Wide bandgap (WBG) semiconductors are one key to the next step toward an energy-efficient world. WBG semiconductors allow for greater power efficiency, smaller size, less mass, and lower overall cost.

Infineon Technologies is offering the broadest product and technology portfolio of silicon (such as SJ MOSFETs, IGBTs), silicon carbide (such as Schottky diodes and MOSFETs) and gallium-nitride-based (e-mode HEMT, Integrated Power Stage) devices. As the leading power supplier with more than two decades of heritage in silicon carbide (SiC) technology development, Infineon Technologies caters to the need for smarter, more efficient energy generation, transmission, and consumption. Their experts understand what is needed to reduce system complexity, leading to decreased system cost and size in mid- to high-power systems.

In the Trenches: CoolSiC^™

Infineon’s goal is to combine the low R_DS(ON)offered by silicon carbide metal-oxide-semiconductor field-effect transistor (MOSFETs) with a gate drive mode device that operates in the safe oxide field-strength conditions. Infineon determined to focus on trench-based devices moving away from planar double-diffused metal-oxide-semiconductor (DMOS) devices with high defect density toward more favorable surface orientations. Trench-based devices enable low channel resistance at low oxide fields. These boundary conditions are the baseline for transferring quality-assurance methodologies established in the silicon power semiconductor world to guarantee failures in time (FIT) rates expected in industrial and even automotive applications. It was out of this work that CoolSiC^™ products were born.

SiC devices operate at much higher drain-induced electric fields in the blocking mode than their Si counterparts (MV instead of kV). Thus, high electric fields in the oxide in the on-state and off-state can accelerate the wear-out. For off-state stress, protection by deep p-regions is adopted. For on-state, a thick oxide is used to circumvent the limits to screen remaining extrinsic oxide defects for thin oxides. CoolSiC^™ products offer unmatched reliability, quality, variety, and system benefits.

CoolSiC^™ MOSFETs trench concepts and benefits include:

Low channel resistance
A safe electric operating field in the gate oxide
Suppresses parasitic turn on
Enables hard commutation and increases surge current robustness
JFET region limits short circuit current
R_ON eases parallel operation
R_g controls and allows independent switching speed

CoolSiC^™ MOSFETs and Diodes

Infineon’s lineup of 650V, 1200V, and 1700V CoolSiC^™ MOSFET devices are ideally suited for hard- and resonant-switching topologies (Figure 1). CoolSiC^™ MOSFETs are built on a state-of-the-art trench semiconductor process optimized to allow for both the lowest losses in the application and highest reliability in operation. The discrete portfolio in TO- and SMD-housings offers on-resistance ratings from 27mΩ up to 1000mΩ. CoolSiC^™ trench technology enables a flexible parameter-set, which is used to implement application-specific features in respective product portfolios, such as gate-source voltages, avalanche specification, short-circuit capability, or internal body diode rated for hard commutation.

Figure 1: 650V CoolSiC™ MOSFET in TO-247 package and 1200V CoolSiC™ MOSFET in D²PAK-7L (Source: Infineon Technologies)

CoolSiC^™ MOSFETs in discrete packages are ideal for both hard- and resonant-switching such as power factor correction (PFC) circuits, bi-directional topologies, and DC-DC converters or DC-AC inverters. An excellent immunity against unwanted parasitic turn-on effects creates a benchmark in low dynamic loss, even at zero volt turn-off voltage in bridge topologies. The transistor outline (TO-) and surface mount devices (SMD) also come with Kelvin-source pins for optimized switching performance.

Infineon CoolSiC^™ Schottky Diodes provide a relatively high on-state resistance and leakage current (Figure 2). In SiC material, Schottky diodes can reach a much higher breakdown voltage. The Infineon portfolio of SiC Schottky products covers 600V and 650V to 1200V Schottky diodes. Combining a fast silicon-based switch with a CoolSiC™ Schottky diode is often termed a hybrid solution.

Figure 2: Automotive qualified CoolSiC^™ Schottky diode. (Source: Infineon Technologies)

CoolSiC^™ MOSFET Modules

Power modules with CoolSiC^™ MOSFET open up new opportunities for inverter designers to realize never-before-seen efficiency and power density levels (Figure 3). Also, Silicon Carbide (SiC) tailors to application needs by different available topologies from 45mΩ to 2mΩ R_DS(ON)per switch. Available in various configurations such as 3-level including ANPC, dual, four-pack, six-pack, or a booster, the SiC MOSFET modules offer superior gate oxide reliability enabled by state-of-the-art trench design, best-in-class switching, and conduction losses.

Figure 3: CoolSiC™ MOSFET Easy1B and Easy2B (Source: Infineon Technologies)

Conclusion

SiC MOSFETs have two distinct structure types: trench MOS and planar DMOS. Infineon is pushing superior trench technology for easy usage in all applications and low-power losses while maintaining reliability. Infineon’s CoolSiC^™ excels in performance and is a benchmark for performance and quality balance. Infineon’s gate-oxide screening process ensures product reliability.

Infineon’s Silicon Carbide CoolSiC^™ MOSFETs and diodes provide a portfolio that addresses the need for smarter, more efficient energy generation, transmission, and consumption. The CoolSiC^™ portfolio addresses customers’ needs for reduced system size and costs in mid- to high-power systems while meeting the highest quality standards, long system lifetime, and guaranteed reliability. With CoolSiC™, customers will reach the most stringent efficiency targets while seeing a drop in operational system cost. Win by being in the trenches—utilize Infineon Technologies CoolSiC^™ solutions.

Wide Bandgap Enhances Power Conversion

Wed, 25 Mar 2020 05:01:00 GMT

(Source: Chaliya/shutterstock.com)

Energy Demand is Increasing

“Save energy” is the mantra we’re all familiar with, but global demand isn’t going to fall anytime soon. According to the Industrial Energy Association, it will increase by about 50 percent until 2040 from 2018 levels. Optimistically, only two-thirds of that increase will be from renewable sources. A bit of mental gymnastics tells us that this means the actual amount from fossil fuels stays about the same. You might think that a future with more renewable energy would mean the efficiency of the conversion process would become less critical. Solar energy, for example, warms the environment whether or not you intercept and convert it to electricity, and eventually heat the load. Energy lost is still money spent unnecessarily, especially with the current higher cost from renewables, so with oil and gas still in the mix with solar, wind, and others for the foreseeable future, the efficiency of the power-conversion process from source to load remains a major issue.

Power Conversion: The Efficiency Challenge

Modern designs using resonant conversion techniques are now so effective that further improvements are down to basic component characteristics, particularly semiconductor switches. The ideal is that they are “off” or “on” in a “switched mode” design, in either case dissipating no power as long as “on” really is a short-circuit. The reality is that even a few milliohms of on-resistance can cause significant losses, and as the transistor slews between on and off states, it produces some transient dissipation. The level of transient dissipation can potentially reach the kilowatts range for a very short period. Keeping losses low therefore means getting that on-resistance lower and the device switching faster so the transient dissipation is for a shorter duration, and for a much lower average value. Traditional silicon-based switches such as IGBTs and MOSFETs are evolving, with incremental improvements, but new materials such as silicon carbide (SiC) and gallium nitride (GaN) are inherently better and are now the great hope for further improvements in efficiency.

SiC and GaN Wide Bandgap Devices Narrow Efficiency Gap

Compared with silicon (Si), SiC and GaN are different right down at the atomic level. The wide bandgap refers to the energy required to move electrons in the material from a “valence band” to a “conduction band” to be available for current flow. SiC and GaN have values about twice those of Si, and the effect on a device fabricated with the materials is dramatic. On-resistance is lower, switching is faster, operating temperature is higher, die areas are smaller and, particularly for SiC, thermal conductivity is far better than for Si or GaN. This means as a combination, less heat is dissipated, and what’s left is effectively led away, making for smaller and more efficient devices. There are knock-on benefits as well: better efficiency means less external cooling; switching faster allows other system components to shrink in size, reducing cost and product dimensions; driving the switches requires far less power than for competing Si devices; and SiC and GaN are inherently radiation hardened (rad-hard). This, along with their high-temperature operating capabilities, makes them suitable for aerospace applications. So, what’s not to like?

Wide Bandgap Semiconductor Uptake is Accelerating

Designers like SiC and GaN, but there are caveats: As they are new technologies, costs have inevitably been higher. These are reducing, and manufacturers are already claiming that overall lifetime cost is lower when system savings are factored in. Also, driving the devices is more critical than with Si and, in some cases, users are waiting for more reliability data before making the change from the more established Si technologies.

In the meantime, SiC and GaN device manufacturers are steadily moving along the evolutionary path, with wide bandgap technology recognized as having some way to go. On-resistances are reducing, voltage ratings increasing, novel packaging arrangements are being used to leverage the device performance to the maximum, and lab and field reliability data are accumulating. Even the sensitive gate-drive concerns are addressed with cascode arrangements of a SiC or GaN device co-packaged with a Si MOSFET for the best of all worlds.

SiC and GaN look to be the future for semiconductor switches, with efficiency gains approaching the theoretical limits set by practical interconnections. That is until the target moves again and the power engineer pulls another wide bandgap rabbit out of the hat.

Why SiC Devices Are Ideal for Level 3 EV Charging Applications

Tue, 24 Sep 2019 15:53:52 GMT

Charging an electric vehicle (EV) can be a lengthy process, usually occurring as an overnight process from a home-mounted AC supply. However, Level 3 “fast” DC charging techniques promise much faster-charging capabilities that reduce charging times to minutes rather than hours. In this blog, we will explore how the efficiency of conversion relies on high-speed power conversion and how new wide-bandgap technologies are well suited for this task.

Charging Time Is as Critical as Range

EV adoption is growing and has the potential to accelerate even faster as potential EV adopters start to do their research. The US Energy Information Administration (EIA) forecasts growth from 2018 to 2050 of 29% for the combined categories of 160.9km, 321.8km, and 482.8km range passenger EVs. Thanks to federal and state initiatives, as well as incentives promoting the viability of owning an electric vehicle, consumers considering buying a new car are far more likely to include an EV option on their shortlist. Whether would-be consumers simply consider it the “right choice for Planet Earth,” or their research takes a more detailed and informed approach, the chances are that range is one of the key selection criteria. Those who drill down a little further then ask the question of how long it takes to recharge the vehicle. The vast majority of vehicle owners equate the recharge process to refueling the vehicle with gas, something that typically takes no more than 10 to 15 minutes. Today, however, most vehicles rely on an onboard AC charging approach that can take overnight or at least many hours (Table 1). Most deployed EV charging infrastructure across the nation is currently Level 1—typically from a home supply—or Level 2—three-phase parking lots and retail locations. The Society of Automotive Engineers (SAE) defined these different levels of charging. SAE standard J1772 sets the charging plug and socket arrangement for Level 1 and Level 2. For Level 2 and Level 3, SAE stipulates a combination plug and socket format.

Table 1: The Types of EV Charging Stations table outlines the levels of EV charging, charging times, and power requirements. (Source: ON Semiconductor)

As Table 1 illustrates, in order to recharge an EV in a duration similar to filling the tank with gas, you need a Level 4 charger and a vehicle capable of being DC-charged. The amount of power involved in Level 4 charging is very high and moves the design emphasis away from the vehicle’s onboard AC-DC charger to a high-power, high-efficiency DC charging infrastructure. Today, Level 4 charging infrastructure is technically possible, but would place significant demands on the local power grid distribution network, which is why Level 3 chargers are a promising solution with their balance of charge time, cost, and grid load.

Designing Level 3 Fast, High-Power Chargers

Level 3 stations, also known as “fast” charging stations, can supply up to a maximum of 500A and require an efficient three-phase power conversion topology for which the Vienna rectifier-based power factor correction (PFC) with a DC-DC converter approach is often used (Figure 1). This method of AC-DC conversion uses three different voltage levels from the grid three-phase supply and is an efficient, high-density, low bill of materials (BOM) method of achieving the desired output power.

Figure 1: The illustration depicts an EV Level 3 charger using a Vienna PFC converter topology. (Source: ON Semiconductor)

Despite the benefits of using the Vienna topology, the need for higher-power conversion switching frequencies and the resultant switching losses, coupled with the need to manage heat generated by conversion losses, can add up. These, together with the space-constraints imposed by charging locations, mean that power-supply design engineers have been searching for semiconductor process technologies that go beyond the current characteristics and properties of silicon-based diodes and MOSFETs.

Wide-Bandgap Devices

Wide-bandgap semiconductor process technologies, such as silicon carbide (SiC), offer fast switching speeds compared to traditional silicon counterparts, which in turn, allows for smaller inductors and capacitors, lowering BOM cost and the amount of board space required (Figure 2). SiC MOSFETs also exhibit much lower RDS_(ON), and hence lower switching loss characteristics, typically a factor of 100 times less than a silicon MOSFET. Overall, SiC devices, thanks to their wider conduction bandgap, have a higher breakdown voltage, typically a factor of 10 times the dielectric field strength of silicon. SiC also has a higher-temperature conductivity, allowing devices to run hotter. Together, all the benefits of using SiC diodes and MOSFETs for a Level 3 charger yield a more compact, higher-efficiency, and higher-performance charging station. The charger circuitry is not only lighter, but the components are likely to cost less too.

Figure 2: The image provides a comparison of material properties and application advantages of SiC devices. (Source: ON Semiconductor)

The ON Semiconductor SiC Portfolio

ON Semiconductor is a leading supplier of SiC-based wide-bandgap diodes and MOSFETs suitable for use in Level 3 chargers. Diodes include 650V and 1200V, available in a wide range of package formats including Decawatt Package (DPAK), TO-220, Direct Bonded Copper (DBC) and baseplate-mounted modules. An example is the FFSH50120A, a 50A, 1200V reverse voltage Schottky SiC diode fabricated in a TO-247-2 package and capable of operating up to +175°C and dissipating up to 730W.

The SiC MOSFET range includes the 1200V automotive grade AEC-Q101 certified N-channel NVHL080N120SC1 through-hole mounting device that can continuously deliver up to 44A and has a maximum RDS_(ON) of 110mΩ.

Silicon carbide-based wide-bandgap diodes and MOSFETs exhibit the perfect performance characteristics for use in Level 3 charging stations. Their high-speed switching credentials, compact dimensions, and robust attributes make them the ideal choice for designing high-power, energy-efficient and compact chargers.

Move Over LEDs, Electric Motors Will Save the Planet

Sat, 01 Dec 2018 05:59:00 GMT

LED lighting is the poster child of environmentalists. And they do have a point. According to the U.S. Department of Energy, solid-state lighting is a highly energy-efficient technology, using 75 to 90 percent less energy, and lasting 25 times longer than traditional incandescent bulbs. The department says that widespread adoption could cut U.S. annual energy consumption by the equivalent of 44 large power stations. LEDs are exciting, trendy, and integrate seamlessly into wireless technology. Consumers, who buy lots of the LED bulbs, feel good about doing their part for the environment. What’s not to like?

Perhaps little. Except that, while consuming a significant proportion—around a fifth—of U.S. electricity generation, lighting is far from the biggest energy consumer. That title goes to an indispensable, yet unexciting technology which works tirelessly behind factory shutters, hidden inside white goods, and lurking behind the floor panels of many autos and in a million other nooks and crannies, out-of-sight and out-of-mind of the public. Yet if we’re serious about saving the planet, we need to turn our collective attention to the largest power consumer of all—the electric motor.

Exact numbers are hard to compile, but U.S. Department of Energy figures from a few years ago revealed that electric motors account for about two-thirds of industrial power consumption and around 50 percent of total U.S. electricity consumption. That’s an incredible 2000TWh each year. Lighting comes in at a distant second, consuming about 19 percent. With numbers that large, even a one percent improvement in electric motor efficiency would eliminate the need for well over 200 large power stations.

While the environmentalists might have overlooked electric motors’ contribution to total energy consumption, engineers have been a little less tardy. To be fair, the techies’ motivation is not wholly altruistic—their customers constantly demand smaller, lighter, longer-lasting motors that are cheaper to run (over its lifetime, the electricity costs incurred by a motor are typically 20 times greater than the unit’s purchase cost)—but the result is the same—greater efficiency leading to lower power demand.

Honing electric motor design

Motor efficiency is determined by how much power is supplied compared with the power the motor generates. For example, if it takes 2W of electrical power to generate 1W of motor power, the unit is 50 percent efficient. The difference (loss) is dissipated in overcoming things like mechanical friction, electrical resistance, and inductive losses. Through many iterations, engineers have honed their designs with innovations such as low-friction bearings, high-permeability magnets, and brushless (induction) firm factors. Contemporary motors boast efficiencies as high as 80 or 90 percent. But a few percent further improvement would have a significant impact on future electricity generating capacity.

Electronic power supplies have also played a major part in the motor revolution. A modern switch-mode power unit produces a three-phase sinusoidal input which in turn produces a rotating magnetic field pulling the device’s rotor around without the use of loss-inducing brushes. In addition, the pulse-width modulation (PWM) superimposed on the base operating frequency enables precise control of parameters such as start-up current, torque, and slip. This precise control of parameters helps to further limit electrical losses.

Now engineers are taking things further:

First, they are favoring high-voltage over traditional high-current designs. This is because nominal motor power is the product of supply voltage and current (V x A). Higher current pushes up the power but also demands the use of larger coils, increasing motor costs and size. High voltages (of the order of 10kV) have the same effect on power but don’t need expensive and heavy copper coils.

Second, engineers are spinning motors faster. Primarily this is because it allows a more compact motor to do the same work as a larger, slower rotating machine, but it also has a small effect on efficiency. For example, increasing the operating frequency limits current ripple—an artifact of the initial rectified mains input and a source of loss—and electromagnetic interference (EMI). High-frequency operation also reduces torque ripple which can cause motor vibration, increased friction, and premature wear.

WBG Semiconductors to the Rescue

A challenge remains; the silicon MOSFETs and IGBTs used as the switching elements in electric motor power supplies are reaching their limits. The problem is fourfold:

The components’ are unable to handle the higher temperatures that come with more stressful operating conditions.

Their relatively low breakdown voltage limits how high engineers can push up input voltages.

Switching losses—caused by residual resistance and capacitance every time a transistor flips from “ON” to “OFF”—increase as the operating frequency climbs (negating efficiency gains elsewhere).

Due to a long switching time, the devices have a relatively low maximum switching frequency.

A savior comes in the form of wide bandgap (WBG) semiconductors. Materials such as gallium nitride (GaN) have a bandgap of 2eV to 4eV compared with silicon’s 1eV to 1.5eV. A band gap is the measure of the energy required to free an electron for conduction in a semiconductor.

Because the electrons of GaN require more energy to escape from an atom and contribute to conduction than those of silicon, the semiconductor is much less prone to unscheduled switching caused by heat build-up rather than the deliberate application of a controlled voltage. GaN also exhibits a higher breakdown voltage than silicon, can switch in about one quarter of the time, and switching losses are around 10 to 30 percent those of a silicon transistor for a given switching frequency and motor current. Finally, because the electrons in GaN are able to move much more freely through the transistor’s crystal lattice than those of silicon, GaN devices can flip much faster.

Commercial GaN solutions are now dropping in price, making them a viable option for cost-sensitive electric motor power supplies—particularly when the end-customer accounts for the motor’s lifetime energy costs as well as its initial purchase price. But part of the take-up of this energy efficient technology will be driven by customer demand. LEDs are more expensive than conventional lighting, but when running costs and longevity are considered, they work out much cheaper than other forms of lighting. That’s why consumers have adopted the technology. Now, it needs appliance manufacturers to sell the same advantages of the GaN-based electric motors in their washing machines and freezers. That way both the consumers and the environmentalists will really have a positive impact on the future environment of the planet.

Bench Talk

Engineering Electronics That Survive Orbit

Understanding the Rigors of Space

Radiation Damage

Designing for Unpredictable Radiation

Current Engineering Approaches

Effects on Earth

Conclusion

How SiC Is Enabling Next Generation Automotive Power Electronics

EV Power Electronics Challenges and the Role of SiC

OBC Architectures: Power Stage Topologies and Semiconductors

Extending OBC Functionality with Bidirectional Charging (V2H)

Optimizing OBC Designs with Top-Side Cooled SiC MOSFETs

From Devices to Systems: Building SiC‑Based Solutions

Author Bio

Why TOLL-8N Is Gaining Momentum in High-Power, High-Density Designs

Start with LCR Basics

What Changes at 650V Compared to Lower-Voltage Switching

Go Kelvin

Packaging Impacts on Cooling

TOLL-8N Package Makes a Difference

Conclusion

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Powering Lanthanide Nanoparticles for NIR II LEDs and Photonics

What Makes Lanthanide Nanoparticles Different

The Second Near‑Infrared Window (NIR‑II)

Hitting an 8‑Electron‑Volt Wall

Stop Forcing Charge—Move Energy Instead

Triplet States: From Optical Waste to Hidden Pathway

Turning Dark States into Light

Pushing the Breakthrough Forward

Conclusion

A Tiny Component with a Large Impact on EV Charging

Why Control Circuits in EV Chargers Are Uniquely Demanding

The Value of Pulse Transformers

A New Approach to Pulse Transformer Design

AMT45S Pulse Transformers in xEV Charging Control Circuits

Conclusion

Author

Mitigating Growing EMI Challenges from High-Efficiency Power Systems

As applications for variable speed motors and battery charging become more widespread, conducted EMI is also increasing, but there are solutions.

High Efficiency as Baseline

How EMI Results from High-Efficiency Designs

Challenges and Mitigation Approaches

Conclusion

Author

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New Tech Tuesdays

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GaN and LEO Connectivity

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The Push for Safer, Smarter Batteries

Graphene Hall Sensors: Mapping Current with Precision

Electrochemical Mass Spectrometry

Physics-based Simulations’ Role in Battery Testing

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New Tech Tuesdays: mMIMO Proves Crucial to 5G

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The Key to 5G

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Not Always a Lack of Charging Etiquette

Scarcity of Chargers

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Compact Convenient Mobile Power

Powering the Future

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Fast PD and USB-C: Universal Charging at Lightning Speeds

Economies of Scale: Delivering Affordability to the Masses

The Newest Products for Your Newest Designs^®

The Newest Products for Your Newest Designs^®

The Newest Products for Your Newest Designs^®

Solution: 1700V_DS, 750mΩ SiC MOSFET

In the Trenches: CoolSiC^™

CoolSiC^™ MOSFETs and Diodes

CoolSiC^™ MOSFET Modules