AFE4900EVM

The AFE4900 is an analog front end (AFE) for optical biosensing applications, such as heart-rate monitoring (HRM) and saturation of peripheral capillary oxygen (SpO2). The device supports four switching light-emitting diodes (LEDs) and three photodiodes. The current from the photodiode is converted into voltage by the transimpedance amplifier (TIA) and digitized using an analog-to-digital converter (ADC). The ADC code can be stored in a 128-sample FIFO with programmable depth. The FIFO depth can be partitioned to accommodate the phases that need to be stored. The FIFO can be read out using either an I²C or SPI interface. The AFE also has a fully-integrated LED driver with an 8-bit current control. The device can be clocked by an external clock or internal oscillator. The device communicates to an external host processor using an SPI/I²C interface. The purpose of the AFE4900 evaluation module (EVM) is to expedite evaluation and system development activities related to the AFE4900 device.

Features

Biosensing AFEs