Q A good way to tell if an op amp is working is to short the

Q: A good way to tell if an op amp is working is to short the + and – terminals together and measure the output. What would be your expectation for the voltage measured at the output of a working op amp in this configuration, and why?

Doesn\'t Vout = A[(V+) - (V-)], therefore Vout would equal 0 if the inputs are equivalent/shorted?

Thanks

Solution

ANSWER:

Yes. You are right. The opamp amplifies the difference in both the inputs. If they are shorted, both the inputs will be at an undefined voltage levels, but equal. Hence, Vout has to be equal to zero.