Hellow Dears ,
I have made a power supply (0-13.5v) range then i want the digital out put 0-13.5v , to achieve this i am using icl7107 with following arrangements but it does not work . All about circuit is shown in attachment .
PROBLEM!
1- When i join this circuit to input 5v to ic and with my power supply ,
the out put varies rendamly .
2- The out put does not depends up on power supply`s output

 

Hmmm...83 people have looked at at this and none have answered. That usually indicates not enough information.

It seems you have left out a connection or put some wire in the wrong place. All I can say from here is, the display requires both positive 5 volts and negative 5 volts and a ground wire. Then it needs 2 wires which bring it the voltage you want displayed. From the way the display is wandering, it would seem that a connection is not completed. See if there are 5 wires feeding the display and check for places you think you made a connection but the connection is loose, then report back here.