ADPD1080/ADPD1081 Photometric Front Ends

ADI’s ADPD1080/ADPD1081 are photometric front ends, each with an integrated 14-bit analog-to-digital converter (ADC) and a 20-bit burst accumulator that works with flexible light emitting diode (LED) drivers. These devices stimulate an LED and measure the corresponding optical return signal. The data output and functional configuration occur over a 1.8 V I²C interface on the ADPD1080 or a serial port interface (SPI) on the ADPD1081. The control circuitry includes flexible LED signaling and synchronous detection.

The analog front end (AFE) features rejection of signal offset and corruption due to modulated interference commonly caused by ambient light without the need for optical filters or DC cancellation circuitry that requires external control.

Couple the ADPD1080/ADPD1081 with a low capacitance photodiode of <100 pF for optimal performance. The devices can be used with any LED. The ADPD1080 is available in a 16-ball, 2.46 mm × 1.4 mm WLCSP and a 28-lead, 4 mm × 4 mm LFCSP. The SPI only version, ADPD1081, is available in a 17-ball, 2.46 mm × 1.4 mm WLCSP. The ADPD1080/ADPD1081 is ideal for clinical measuring, industrial monitoring, and fitness monitor applications.