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The operational amplifier

The op amp is a very useful component because it has:
(a) a high open loop voltage gain (Ao) - up to 105 for d.c.
(b) a very high input resistance
(c) a very low output resistance
(d) it is a differential amplifier

Output voltage of an op amp (Vo) = Ao(V2- V1)
© Keith Gibbs 2009