Previously we made Digital Voltmeter using PIC16F688,but now we made the same digital voltmeter using ICL7107.We have used ICL7107 because it displays both positive and negative voltages and the second reason to use this IC was that it is cheaper than the PIC16F688 which was used earlier and no programing is required for ICL7107.
The datasheet of ICL7107 can be downloaded by:clicking here
We wasted almost 2 week on making Digital voltmeter by taking help of below mentioned site and then we modified the circuit and made it work.Digital Voltmeter we made is used for measuring the output voltage of your DC power supply and include 3.5-digit LED display with negative voltage indicator.This circuit should be supplied with a 5v voltage supply and consumes only around 25mA.
You can find the link by:clicking here
Here is the modified circuit and the JPEG download of the circuit:click here
