Post Go back to editing

Connecting 3 LEDs Red, Green IR to ADPD105


I am working on testing of EVAL-ADPD105. ADPD105 Supports connecting 3 LEDs through LEDX1, LEDX2, LEDX3. I want to connect Red, IR, Green LED to these pins. But based on the register configuration we can enable only 2 LEDs in a particular time slot based on register configuration in 0x14. 

If We want to control the 3rd LED How can be do that. 

  • Hi there,

    The ADPD105 operates two independent time slots, Time Slot A and Time Slot B, allowing two measurements. You can only enable one LED driver in either Time Slot A or Time Slot B by setting proper bit in register 0x14. Unfortunately the ADPD105 does not support a third time slot hence you have to connect at least two LEDs of different color to a single LED driver if your application allows.

    We encourage you to take a look at our latest photometric AFE ADPD4100 ( The ADPD4100 support up to 12 time slots and can enable up to 4 LED drivers during any time slot for fine control of the LED current.


    Glen B.