Another virtual gnd question

Discussion in 'The Projects Forum' started by snav, Mar 23, 2014.

  1. snav

    Thread Starter Active Member

    Aug 1, 2011
    I'm building this circuit and was wondering if a red&grn leds could be used from pin 7 to pin 8 as a duty cycle indicator. The output is rated at 20ma and I would plan to run the LEDs on 1-2ma with only one running at a time it would be minimal load. I was thinking the Vref(virtual gnd) isn't doing much work but maybe 2ma might throw the Vref off? Has anyone done this? Hints?
  2. #12


    Nov 30, 2010
    An LM324 can drive 2 ma but you might want to put a filter on it so it doesn't jiggle the virtual ground. That might cause feedback problems in the oscillators.
    snav likes this.