dipping of voltage when reset button in ATMega32 is switched on

Discussion in 'The Projects Forum' started by svsandeep99, Mar 2, 2011.

  1. svsandeep99

    Thread Starter New Member

    Mar 8, 2009
    hi guys,
    i am working on ATmega32 micro controller for my project. in my project i am controlling the number of step of a PMSM(permenent magnent syn machine).
    i am controlling in such a manner that if i keep 5v( i am using ADC for controlling my steps) my machine should run 250 steps and the no of steps are varied according to the voltage i apply to ADC. so if keep 1v my machine should move 50 steps( 5v it move 250 steps it has a linear proportion) and it is running successfully and i am generating 5v from 7805 and i am varying this voltage at ADC with a potentiometer for controlling my steps. But the problem is that if i keep 4v at ADC by using potentiometer(POT) with reset button in off position, when i am tunning on my reset swith the voltage across ADC pin is falling down from 4v to 3.5v, so it is reducing the steps to be moved. i got the problem bez of potentiometer(loading effect) it is falling. so how can i maintain same voltage when reset button is on or off.
    plz help me guys