Hello,
I was trying to change Vref to read smaller voltages, but as I supply smaller voltage to the Vref pin, it's always 3.3v. I can't find anything to configure this pin or so, to be able to change it. If you have anything that may help, please let me know. Thanks, Hashem
The lowest VREF allowed for LPC23xx is 2.5V. With a 10-bit ADC, that still leaves you at 2.5mV steps (can I assume that you did check the datasheets?). So this would be a good time to stop experimenting with the voltage reference and instead condition your signal.