Hi,
I am currently testing a prototype board with an AFE4490 module.
When I look at the ambient light signal of the RED and the ambient light signal of the IR LED than I see a DC offset difference.
This difference is not there when I disable the second stage amplifier. It only appears when I enable the second stage.
When I detach the photo diode from the board than the DC offset still exists, but the difference is a little less.
The TIA_GAIN and the TIA_AMB_GAIN settings for both LEDS are equal.
Does someone have a similar experience with this issue?
Regards,
Martin