1 Features
1• Supports signal acquisition of up to 24 phases
• Flexible allocation of 6 LED, 4 PD in each PPG
phase
• Synchronized PPG/ECG signal acquisition with
each phase configurable as PPG or ECG, and at
different data rates
• Synchronized PPG/ECG supports up to 1 kHz
data rate
• ECG-only mode supports up to 4 kHz data rate
• PPG signal chain:
– 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
• PPG 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
• PPG Receiver:
– Supports 4 time-multiplexed photodiode inputs
– 2 parallel receivers to sample two PD channels
simultaneously
– 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
• ECG Signal Chain
– 1-lead ECG with RLD output for bias
– INA gain programmable from 1.6 – 13
– <1 μVrms input noise (in a 1-150 Hz
bandwidth) at 4-kHz sample rate
– Integrated 450 Hz Low Pass Filter
– AC, DC lead-off detect with 3.125-100 nA
current and programmable interrupt
• 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
• Supports operation with 2 supplies - 1.8 V, 5 V

2 Applications
• ECG on a wearable device
• Synchronized PPG, ECG for PTT-based Blood
pressure
• Optical heart-rate monitoring (HRM) and Heartrate
variability (HRV) for wearables, hearables
• Pulse oximetry (SpO2) measurements
• Maximum oxygen consumption (VO2 Max)

3 Description
The AFE49I30 is an analog front-end for optical biosensing/
PPG and ECG measurement applications.
The device supports up to six switching light-emitting
diodes (LEDs) and up to four photodiodes. Up to 24
signal phases can be defined and the PPG or ECG
signals can be acquired from each phase in a
synchronized manner.