here is a small project of Analog to Digital Converter using ATmega32 which is having on-chip 8-channel ADC.
The circuit also consists of an intelligent 16x2 LCD for displaying the value of the voltage applied at each channel. There is also a push-button to scroll throgh the different channels. The schematic is as shown in the figure:
When powered on, the LCD displays"ADC Testing.." on the first line and the value of the voltage applied at the channel0 on the second line. When the push-button is pressed, the second line displays the value of channel1. Like-wise, all the channels can be checked one-by-one by pressing the push-button. The channel count will roll back to channel0 after going to channel7.
The displays shown in the pictures on top show values at channel0 and channel1. Here a AA battery was connected to channel0 and the channel1 was connected with the +5v supply.
A 9-pin connector is used for ADC, 8 ADC channel pins and 1 ground pin. (the values displayed on LCD will fluctuate for a channel if nothing is connected to that channel)
The software is created in C using ImageCraft ICCAVR compiler.
The Schematic and code for this project can be downloaded here:
Download Schematic and Code
Download HEX file