Discussion in 'General Electronics Chat' started by armen323, Oct 19, 2009.

  1. armen323

    Thread Starter New Member

    Oct 14, 2009

    I am working on a project with a keypad recording device. The problem that i am having is this. When i test the device pins, the pins that are connected to the keypad matrix it gives me Mv ranges that are too high. There is a very small amount of current in those pins for example when i use the multimeter and put the + on pin 1 and the - on pin 3 the Mv rating is just to high, in some instances it even gives me a voltage rating of about 3.6 v which is the same voltage battery (3.7) on the device it self.

    I can not do any circuits changes or additions to the device it self, my question is this.

    What can i use to filter out this current, can? Can another device be created to be attached to the recording device so it can clear out the current?

    Please help.

    Thank you,

  2. beenthere

    Retired Moderator

    Apr 20, 2004
    If the mystery device is a microcontroller, the input pins may be set to a HIGH state. If the keypad pulls those pins LOW when used, there won't be a problem.

    You might tell us more about the "device".