ADPD105 Photometric Front End with I2C

The ADPD105/ADPD107 are highly efficient, photometric front ends, each with an integrated 14-bit analog-to-digital converter (ADC) and a 20-bit burst accumulator that works in concert with flexible light emitting diode (LED) drivers. It is designed to 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 ADPD105 or SPI on the ADPD107. 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.

Couple the ADPD105/ADPD107 with a low capacitance photodiode of <100 pF for optimal performance. The ADPD105/ ADPD107 can be used with any LED. The ADPD105 is available in a 2.46 mm × 1.4 mm WLCSP. The SPI only version, ADPD107, is available in a 2.46 mm × 1.4 mm WLCSP.

Applications
  • Wearable health and fitness monitors
  • Clinical measurements, for example, SpO2
  • Industrial monitoring
  • Background light measurements
Features and Benefits
  • Multifunction photometric front end
  • Fully integrated AFE, ADC, LED drivers, and timing core
  • Enables best-in-class ambient light rejection capability without the need for photodiode optical filters
  • Three 8 mA to 370 mA LED drivers
  • 2 optical inputs
  • Flexible, multiple, short LED pulses per optical sample
  • 20-bit burst accumulator enabling 20 bits per sample period
  • On-board sample to sample accumulator, enabling up to 27 bits per data read
  • Low power operation
  • SPI, I2C interface and 1.8 V analog/digital core
  • Flexible sampling frequency ranging from 0.122 Hz to 3.820 kHz
  • FIFO data operation
  • Optical
    Data Sheets
    Documentnote
    ADPD105/ADPD107: Photometric Front Ends Data Sheet (Rev. 0)PDF 1.11 M
    User Guides
    Documentnote
    UG-1021: Evaluating the ADPD105 Photometric Front End (Rev. 0)PDF 1.93 M
    Order Information
    Part NumberPackagePacking QtyTemp RangePrice 100-499Price 1000+RoHS
    ADPD105BCBZR7 ProductionCHIPS W/SOLDER BUMPS/WLCSPREEL 3000-40 to 85C02.51Y
    Evaluation Boards
    Part NumberDescriptionPriceRoHS
    EVAL-ADPD105Z-GENADPD105 Generic Evaluation board135Y
    ADPD105/ADPD107: Photometric Front Ends Data Sheet (Rev. 0) adpd105
    UG-1021: Evaluating the ADPD105 Photometric Front End (Rev. 0) adpd105