I use an ad7680 to measure 0-5V DC signal.This ADC is interfacing with PIC32MX795F512L, with SPI interface.
The supply of the ADC is 5V.
I have a problem with this ADC, when my analog signal increase 0 to 2.5 V the digital output increase 0 to 65535.
After when my signal increase from 2.5V to 5V the digital output increase 0 to 65535.
Normally , i think that the digital output should increase from 0 to 65535 when the anlog input increase 0 to 5V.
Is anyone have this problem ? Can you help me.
Excuse me for my bad english.