Features and Benefits

  • 2.8 mm × 6.5 mm module with integrated optical components
    2 green LEDs located on either side of the photodiode, 1 infrared LED, and 1 photodiode
  • True 3-channel 250 mA LED driver
  • Separate LED and AFE settings for each channel
  • Dual data registers for each LED return signal
  • 14-bit ADC
  • 20-bit burst accumulator enabling 20 bits per sample period
  • On-board sample to sample accumulator enabling up to 27 bits per data read
  • Custom optical package made to work under a glass window
  • Optimized SNR for signal limited cases

Product Details

The ADPD174GGI is a complete photometric system designed to measure optical signals from ambient light and from synchronous reflected LED pulses. Synchronous measurement offers best-in-class rejection of ambient light interference, both dc and ac. The module integrates a highly efficient photometric front end, three LEDs, and a photodiode (PD). All of these items are housed in a custom package that prevents light from going directly from the LED to the photodiode without first entering the subject.

The front end of the ASIC consists of a control block, a 14-bit analog-to-digital converter (ADC) with a 20-bit burst accumulator, and three flexible, independently configurable LED drivers. The control circuitry includes flexible LED signaling and synchronous detection. The analog front end (AFE) features best-in-class rejection of signal offset and corruption due to modulated interference commonly caused by ambient light. The data output and functional configuration occur over a 1.8 V I2C interface.


  • Optical heart rate monitoring
  • Reflective SpO2 measurement

Complete documentation is available upon completion of a Non-Disclosure Agreement (NDA) (pdf).  Send your completed forms by e-mail to optical_sensors@analog.com. Additional support is available from your Analog Devices local sales.

Please contact the Optical Sensors Team for additional technical information.

For additional ADI Healthcare Products and related information, please visit www.analog.com/healthcare.

Product Lifecycle icon-not-recommended Not Recommended for New Designs

This designates products ADI does not recommend broadly for new designs.