Icl 7107 volt meter

Discussion in 'The Projects Forum' started by Allan Brown, Oct 3, 2009.

  1. Allan Brown

    Thread Starter New Member

    Aug 2, 2009
    I have reconstructed a digital panel meter from LCD to led. But it will not
    read any voltage, shorting the input it registers 00.0 and alternates mines
    on and off. input open it displays the dp and the one. Can any one give me
    any suggestions as to what is wrong.

    Thank you in advance A. Brown
  2. bountyhunter

    Well-Known Member

    Sep 7, 2009
    Sounds like an over range. On those IC's, they were 200mV full scale as I recall (?). Measure the voltages and see what the meter inputs are getting.
  3. beenthere

    Retired Moderator

    Apr 20, 2004
    From the data sheet, the ICL7107 is designed to run LED displays. If you were using an ICL7106 made to use LCD, then that might explain the problem.

    Otherwise, can you post up the schematic for the complete meter?