AFE44I31YZT

Analog Front End (AFE) Overview

The AFE44I31YZT is an analog front-end for optical bio-sensing applications, including heart-rate monitoring (HRM) and pulse oximetry (SpO2). It supports up to six switching LEDs and four photodiodes with up to 24 signal phases. The device integrates a transimpedance amplifier (TIA), ADC, and a 128-sample FIFO. Key electrical parameters include a system SNR of up to 108 dB at 16 μA PD current, LED current range of 25 mA to 250 mA, and ambient rejection close to 100 dB up to 10 Hz. Supplies are 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.

Analog Front End (AFE) Feature Summary

• Supports signal acquisition of up to 24 phases with flexible allocation of 6 LEDs and 4 PDs per phase.
• Integrated transmitter with 8-bit programmable LED current control ranging from 25 mA to 250 mA.
• Receiver features two parallel TIA/filter sets with individual ambient and LED offset subtraction DACs.
• Includes a 128-sample depth FIFO and I2C interface for data readout.

Analog Front End (AFE) Applications

• Optical heart-rate monitoring (HRM) for wearables and hearables
• Heart-rate variability (HRV)
• Pulse oximetry (SpO2) measurements

Analog Front End (AFE) Procurement Notes

Verify the specific ordering suffix 'YZT' against the official Texas Instruments orderable addendum to confirm package type, pin count, and manufacturing status. Ensure compatibility with the required supply voltages and interface protocols before procurement.

Analog Front End (AFE) Selection Notes

Select this component for multi-sensor wearable designs requiring simultaneous signal acquisition at different data rates. Consider the DSBGA package size and operating temperature range (-40°C to 85°C) for integration into compact devices.

Analog Front End (AFE) Part Context

The AFE44I31 belongs to the AFE44I30 family of ultra-small integrated analog front-ends designed for optical bio-sensing. It shares core functionality with the AFE44I30 but may differ in specific ordering or packaging details as defined by the manufacturer's product folder.

Analog Front End (AFE) Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. Consult the TI product folder for potential alternatives within the AFE44xx family based on channel count and performance requirements.