1 Features

1• Supports signal acquisition of up to 24 phases

• Flexible allocation of 6 LED, 4 PD in each phase

• Simultaneous signal acquisition from different

sensors at different data rates

• Accurate, continuous heart-rate monitoring:

– System SNR up to 108-dB at 16 μA PD current

– Low current for continuous operation on a

wearable device with a typical value: 15 μA for

an LED, 20 μA for the receiver

• Transmitter:

– Supports common anode LED configuration

– 8-Bit programmable LED current with range

adjustable from 25 mA to 250 mA

– Mode to fire two LEDs in parallel with

independent per-phase current control

– Programmable LED on-time per-phase

– Simultaneous support of 6 LEDs for SpO2,

HRM, or multi-wavelength HRM

• Receiver:

– Supports 4 time-multiplexed photodiode inputs

– 2 parallel receivers (two sets of TIA/filter)

– Individual ambient offset subtraction DAC at

each TIA Input with 8-bit per-phase control and

range adjustable up to 255-μA

– Individual LED offset subtraction DAC at each

TIA input with 5-bit per-phase control and 15.5-

μA range

– Close to 100 dB ambient rejection up to 10 Hz

– Noise filtering with programmable bandwidth

– Transimpedance Gain: 3.7 kΩ to 1 MΩ

• Supports external clock and internal oscillator

modes

• Option to acquire data synchronized with a system

master clock

• Automatic cancellation of DC from ambient, LED

• FIFO with 128-sample depth

• I2C interface

• 2.6-mm × 2.1-mm DSBGA, 0.4-mm pitch

• Supplies: Rx: 1.7 V-1.9 V (LDO bypass); 1.9 V-3.6

V (LDO enabled), Tx: 3 V-5.5 V, IO: 1.7-3.6 V