Texas Instruments AFE1598 Analog Front-Ends (AFEs)
Texas Instruments AFE1598 Analog Front-Ends (AFEs) are multichannel, simultaneous-sampling, 24-bit delta-sigma analog-to-digital converters (ADCs) for biopotential measurements. These devices integrate programmable-gain instrumentation amplifiers, an internal reference, an on-chip PLL, and eight high-resolution ECG channels. The flexible architecture supports eight leads selected from ten electrodes and provides a programmable gain range of 1.25 to 9.
The TI AFE1598 AFEs feature DC lead-off detection, AC lead-impedance detection, battery-voltage monitoring, test signals, and a steerable right-leg-drive amplifier. A built-in oscillator, flexible power-down and standby modes, SPI-compatible communication, and a 1k-sample main FIFO help simplify system implementation. Multiple AFE159x devices can be cascaded for systems requiring higher channel counts.
The AFE1598 devices target medical instrumentation, including ECG, EMG, and EEG equipment, portable telemetry, patient monitoring, event monitors, and sleep-study systems. These AFEs are available in QFN and WCSP package options and support systems designed to meet applicable AAMI and IEC medical equipment standards.
Features
- Integrated signal chain for ECG and biopotential measurements
- Eight high-resolution channels with simultaneous sampling
- Flexible eight-lead selection from ten electrodes
- Built-in programmable-gain instrumentation amplifiers
- DC lead-off detection and AC lead-impedance detection
- Wilson Center Terminal and Goldberger Central Terminals
- Built-in right-leg-drive amplifier steerable to any electrode
- Battery-voltage monitoring and internal test signals
- Integrated oscillator, PLL, and reference
- Flexible power-down and standby modes
- 1k-sample main FIFO
- Cascading support for high-channel-count systems
- Supports systems meeting AAMI EC11, AAMI EC13, AAMI EC38, IEC 60601-1, IEC 60601-2-25, IEC 60601-2-27, and IEC 60601-2-51 standards
Applications
- Event, stress, and vital sign monitors:
- ECGs
- AEDs
- Telemedicine Bispectral Index (BIS)
- Evoked Audio Potential (EAP)
- Sleep study monitor
- Medical instrumentation (ECG, EMG, and EEG):
- Bedside patient monitoring and diagnostic ECG
- Portable telemetry
- Holter monitor and multi-lead patch
Specifications
- Eight ECG channels
- 24-bit delta-sigma ADC architecture
- Power consumption of 0.37mW per channel
- Programmable gain range of 1.25 to 9
- Noise of 4.7µVPP in a 150Hz bandwidth at a gain of 4
- Differential input voltage range of ±1V at a gain of 4
- Common-mode rejection ratio of -140dB
- Data rate range of 125SPS to 128kSPS
- SPI-compatible serial interface
- Analog supply voltage 1 range of 3.15V to 5.25V
- Analog supply voltage 2 range of 1.7V to 1.9V
- I/O supply voltage range of 1.65V to 3.6V
- Operating temperature range of -20°C to +85°C
- QFN package dimensions of 8mm x 8mm
- WCSP package dimensions of 3.6mm x 5.2mm