Tech Note 143 - ESP32 – Voltage Reading (pre-calculated voltage divider) Examples

How to measure voltages using the ESP32 ADC. Here I have pre-calculated a range of voltage dividers to measure voltages from 0 - 5v, 0 - 6v, 0 - 12v, 0 - 15v, 0 - 24v, 0 - 50v and 0 - 100v. Because the input impedance of the ESP32 loads the voltage divider, you have to compensate the readings accordingly and I explain how to do that, including pre-calculated factors so you don&have to work anything out!