ESP32-S2-SOLO-U-N4: Boots only at second power-on

[Davelec]

Hello ESP32 community,

I have designed a custom PCB with the ESP32-S2-SOLO-U-N4. Everything works fine except when I power-on the device after at least 2 minutes of OFF-time the ESP doesn't boot. When I power-off and power-on again everything is working fine.

At first I thought that the 3,3 V supply is rising to slow so that there is an issue with the reset. But looking at the oszilloscope everything looks the same at the first and at the second power-on. I have added the schematic and a screenshot from the oszilloscope.

Does anyone have an idea? For me it seams like there some Caps are loading too slow when they are completely empty at first power-on...

[ESP_Sprite]

The 100n over the GPIO0 button likely makes the ESP32 go into download mode in the situations where it 'doesn't boot'. Remove that and the issue should go away.

[Davelec]

Thank you very much. That fixed the problem. Too easy