The AFE4500 evaluation module (EVM) is designed to expedite evaluation and system-development activities related to the AFE4500. AFE4500 supports synchronized signal acquisition for photoplethysmogram (PPG), electrocardiogram (ECG), and body impedance analysis (BIA).
The analog-to-digital converter (ADC) output of all three signal chains is stored in a 256-sample, first-in first-out (FIFO) block that can be read out using a serial peripheral interface (SPI) or I2C interface. The chip has separate signal chains for PPG, ECG, and Bio-Z testing that share the same ADC. Separate signal acquisition windows can be defined to acquire the PPG, ECG, and/or Bio-Z signals. The acquisition rate of each signal can be independently set. Simultaneous acquisition of up to 24 PPG signals involving up to 8 LEDs and up to 4 PDs are supported, thereby enabling applications like optical heart-rate monitoring (OHRM) and pulse oximetry.
The analog front end (AFE) supports multiple-signal acquisition modes, including a PPG-only mode and two mixed acquisition modes, each of which allows any combination of signals to be acquired.
- Acquire data at up to 1000 SPS in evaluation mode
- USB-based power and PC application connectivity
- Access to all AFE4500 registers
- USB-based firmware upgrade option