External clock source for ESP32-PICO-V3

[Ivan32]

Is it possible to provide an external clock signal to the ESP32-PICO-V3 chip?

We have few other MCUs on the board and a centralized high-quality 40MHz crystal on it. Particularly, it defines audio sampling rate, which we would like to send over Bluetooth A2DP to the speakers using ESP32.

But if ESP32 chip has its own clock, it will be slightly off from our audio sampling rate and audio quality will be poor (we cannot use I2S reference clock from the ESP32).

All ESP32 datasheet reference designs show crystals connected to pins 44 and 45, but at the same time they say that they are NC. Are they indeed NC or we can still provide our clock to say 45(XTAL_P)? That would be great!

[ESP_Sprite]

I don't think so. The fact that the datasheet states NC there means that even if there is a connection you can feed a clock signal into, you cannot rely on a future revision to also have it. Suggest you go with a bare ESP32 instead.