Hi,
I hope you are doing well.
We're encountering issues with the EVAL-ADPD4100Z-PPG while trying to interface it with an external MCU (STM32) via SPI. Our MCU operates at 3.3V, so we made the following modifications to match the board's IOVDD to 3.3V:
- Set JP2 to VDD_3V mode
- Removed R1
- Removed E1
Despite these changes, we couldn't establish communication with the IC. We initially suspected our manual breakout, so we reverted these modifications and used a logic level converter (1.8V to 3.3V), which functioned correctly. After reverting to the original modifications, we noticed that the CS line was still being pulled high to 1.8V despite the removal of R1 and setting the IOVDD pin to 3V3.
Could you help us understand why the CS line behaviour persists and suggest any further modifications to correct this?
Thank you.
