ADC max input voltage?

[torntrousers]

Hi, can anyone tell me the absolute maximum input voltage of the ESP32 ADC pins? I've seen a few blog posts suggesting 4.0 volts but I can't see that any any Espressif docs.

Also, does that change with the ADC attenuation setting?

Thanks!

[onehorse]

I assumed it was 3V3, but I haven't seen it documented anywhere. But 3V3 seems consistent with my experience using in, at least on pin 34!