Description

Multimodal Sensor Front End Features: Optical channel 4 input channels with multiple operation modes for various sensor measurements Dual channel processing with simultaneous sampling 12 programmable time slots for synchronized sensor measurements Flexible input multiplexing to support single-ended sensor measurements 4 LED drivers, 2 of which can be driven simultaneously Flexible sampling rate from 0.004 Hz to 9 kHz using internal oscillators SNR of transmit and receive signal chain: 117 dB (with off-chip filtering) AC ambient light rejection: 78 dB up to 100 Hz 400 mA total LED peak drive current Individual ambient light rejection DAC at TIA input with 9-bit control up to 300 μA Individual LED dc cancellation DAC at TIA input with 7-bit control up to 190 μA ECG channel 0.75 μV rms RTI noise at diagnostic filter bandwidth (150 Hz) High input impedance: 3 GΩ Accepts up to 1.2 V of dc differential input range Common-mode rejection ratio: 116 dB Two-electrode and three-electrode configurations AC lead off detection and dc lead off detection BIA channel Low power, high accuracy excitation path Configurable output frequency up to 250 kHz Sine wave excitation with a 12-bit DAC High accuracy with large imbalance contact impedance Configurable receive filters with low noise design Complex impedance measurement engine Supports both external calibration and internal calibration SPI communications supported 640-byte FIFO