The definition of "input offset voltage" is the differential voltage which is required to apply between the two terminals of the op-amp such that the output of the op-amp will become zero.
What I want to learn is: Imagine we have an opamp buffer and we apply(at its non-inverting input) a very well known constant precise voltage 1.0000V for instance and we measure 1.0015V meaning that there is 1.5mV offset. What is this offset voltage called? And does it have any relation with "input offset voltage"?
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