AFE4960PEVM: How to save raw RED/IR data (and DC values) for SpO₂ calculation

Hi Experts,

I am using the AFE4960P EVM to capture PPG signals for SpO₂ calculation. I would like to export the raw RED and IR photodiode data so I can compute the AC/DC ratio offline.

However, I see a mismatch between what is plotted and what is saved:

• The AFE4960P GUI plots RED-AMB / IR-AMB in mV, but the exported CSV does not contain mV values.

• In the Bio-Sensing (Asterix) GUI, I can change FIFO channels to RED / IR, but the exported values appear scaled, not raw ADC values or mV.

My questions:

1. What is the correct way to export raw RED and IR samples suitable for offline SpO₂ calculation?

2. Is it possible to export the same mV values that are shown in the AFE GUI plot?

3. If export always gives scaled data, what is the recommended conversion method to obtain:

   • raw ADC code

   • volts / mV (matching the GUI)?

4. Does the AFE4960 internally compute the DC component of RED/IR?

   • If yes, how can I access or log the DC value?

   • If no, should I extract DC from the raw waveform manually?

My goal is to verify AC/DC extraction and SpO₂ ratio offline and ensure the proper data logging and scaling.

Regards,

Marvin