ESP32-SOLO-1 flash failure - possible VDD_SDIO issue

[ns1668]

Hi there,
We are currently having an issue with flashing the module from a host MCU.

Can someone confirm what the operating voltage of the internal flash chip is, 3.3V or 1,8V?

I checked the technical reference manual, esp32 datasheet and the solo-1 datasheet but there is no mention of the operating voltage for the solo 1 module, is there an official reference for this please?

I want to make sure we have the bootstrapping for MTDI configured correctly.

Thanks

[ns1668]

I've scoped the MTDI pin on our design and its pulled to GND by default, which I assume is the correct voltage for the integrated flash on the SOLO-1 modules.

Any thoughts on this?