Analog Devices Inc. MAX49921 Current-Sense Amplifier (CSA)

Analog Devices MAX49921 Current-Sense Amplifier (CSA) is optimized for current monitoring of inductive loads, such as DC motors and solenoids, where common-mode voltages can become negative due to inductive kickback, reverse-battery conditions, or transient events. The MAX49921 features an operating input common-mode range from 0V to +70V, and the device is protected against input common-mode voltages down to -42V and up to +80V. This design protects against reverse- battery and high-voltage spikes.

The low input offset of ±0.5μV (typical) and low gain error of ±0.05% (typical) make the unidirectional MAX49921 CSA ideal for high-precision current measurements.

The Analog Devices MAX49921 operates from a supply voltage of +2.7V to +5.5V with a typical quiescent supply at 0.7mA. This device is specified over the -40°C to +125°C automotive temperature range and is AEC-Q100 qualified. The Analog Devices MAX49921 CSA is offered in a 2mm x 3mm, side-wettable TDFN8 package with gain options of 20V/V and 50V/V.

Features

  • AEC-Q100 qualified for automotive applications
  • 7V to 5.5V supply voltage
  • 7mA (typical) supply current
  • ±0.5μV (typical) input offset voltage
  • ±0.05% (typical) gain error
  • 0 to +70V input voltage range
  • -42V to +80V protective immunity
  • 65kHz, -3dB bandwidth
  • 140dB DC CMRR
  • 20V/V and 50V/V gain options
  • Rail-to-rail output
  • -40°C to +125°C automotive temperature range
  • 2mm x 3mm TDFN8 package
  • RoHS compliant

Applications

  • Solenoid current sensing
  • Battery current monitoring
  • Current monitoring of inductive loads
  • High- and low-side precision current sensing
  • Super-capacitor charge/discharge monitoring
  • Precision high-voltage current monitoring
  • Automotive current sensing

Videos

Block Diagram

Analog Devices Inc. MAX49921 Current-Sense Amplifier (CSA)

Typical Application Circuits

Application Circuit Diagram - Analog Devices Inc. MAX49921 Current-Sense Amplifier (CSA)
Published: 2020-12-07 | Updated: 2024-07-31