Olimex Support Forum

Microcontrollers => ESP32 => Topic started by: paulmullen on June 14, 2024, 06:40:36 AM

Title: How to make the value stable?
Post by: paulmullen on June 14, 2024, 06:40:36 AM
Hello,

I have a olimex esp32 poe board, and I am reading an potentiometer (0-3.3V) value, however there is this ripple on the + of the potentiometer(red) which is also visible on the adc of the esp32 (yellow)

i have already added an 10nF capacitor close to the input, and a bigger one, which does not help unfortunately.merge fruit (https://mergefruit.io)
This significant ripple only appears when the poe power supply is connected(HP1820 J9982A)

How can I make the value stable without sacrificing a lot of hysterysis on my adc input?

Thanks in advance
Title: Re: How to make the value stable?
Post by: LubOlimex on June 14, 2024, 08:54:49 AM
What exactly is the board that you have? Base ESP32-POE? Which hardware revision?

Can you upload somewhere few pictures of the ripple and share here?