ESP32 Forum

Have a nice day!
Tell me about the wiring of the earthen tire for ESP 32-WROOM-32D. I use the ADC on pins 5 and 6. To reduce interference, I do not use pins 4 and 7, assigned them as inputs and put them on the ground, resulting in an earthen barrier around the ADC inputs. I know that the analog and digital earth should be combined at 1 point. But the ESP 32 has several ground pins. Which is the best way to get an analog ground so that there is as little interference as possible?

Generally, if you don't have a specific purpose, you can connect both analog and digital grounds to the same ground plane. The noise is coupled through a common impedance. The purpose here is to reduce the impedance and so the noise. Impedance is mainly resistive for low frequency and mainly inductive for high frequency. So using a solid ground plane is a good idea. It will prevent signal return path discontinuties (split planes) as well.

https://link.springer.com/chapter/10.10 ... 14186-7_14
https://link.springer.com/chapter/10.10 ... 14186-7_16

ESP32 chip has one ground pin (central pad) by the way.