Non-ideal op amp parameters

Discussion in 'Homework Help' started by Peytonator, May 27, 2009.

  1. Peytonator

    Thread Starter Active Member

    Jun 30, 2008
    Hi there,

    I have a few questions:

    1) Say I have the LH0032C op amp with the following specs:
    Vio = 15mV - input offset voltage
    Iio = 50pA - input offset current
    Ib = 500pA - bias current
    Given certain resistor values, the questions asks me for the worst case dc offset voltage that will appear at the ouput of the amp. I can easily calculate the offset voltage at the output due to all 3 of the above specs. But is the worst case the addition of all 3 calculated values, or the greatest of the three?
    Also, is the ouput then = gain*Vin +/- worst case offset voltage.

    2) General question relating to op amps:
    Say I have an error voltage Ev, due to temperature changes. What is this error voltage? Is the output = gain(Vin) +/- Ev

    Help would be much appreciated :)

  2. mik3

    Senior Member

    Feb 4, 2008
    The worst case is the output offset voltage due to the three factors affecting the input offset voltage.