Description
Hi,
I checked yesterday the new implementation of analogRead and values are pretty incosistent. Not sure if it is because of the implementation of the method or just because the ADC on ESP32 is not very accurate.
I created a simple several stage voltage divider to read on. Source was the 3.3V output pin of the ESP WROOM 32. Then I applied 3 different steps with 4.7K 1% tolerance resistors. Values measured with the multimeter:
P1: 3.286V --> Expected = 4095 / ADC output = 4095
P2: 2.462V --> Expected = 3071 / ADC output = 2811
P3: 1.641V --> Expected = 2047 / ADC output = 1814
P4: 0.819V --> Expected = 1021 / ADC output = 823
Any explanation to this? I though the levels would go from 0 being 0V and 4095 being top of the range 3.3V
I need to rely on an accurante ADC for my project so any help is welcomed. Cheers!