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What happens if you force a different voltages into opamp?

  1. Oct 2, 2007 #1
    The professors have taught you that in an opamp, the voltage in one terminal is equal to another.

    Suppose you put a 5V voltage source in one terminal and 2V voltage source in the other. What happens then?
  2. jcsd
  3. Oct 2, 2007 #2


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    Operational amplifiers are differential. i.e. they are based on the voltage difference of the inputs.

    Check out these collection of circuits to see how the inputs are used.
  4. Oct 3, 2007 #3


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    only if there is negative feedback (correctly wired up from VOUT to the V- terminal usually through some resistance).

    the op-amp output is saturated (hits the rail) at either +VCC or -VCC (depending on which of the V+ or V- inputs gets connected to the more positive voltage).
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