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I am wondering how applying a negative voltage to an op-amp's inputs has any effect on the output at all when both inputs are connected to NPN transistors which require a positive voltage to conduct. A negative voltage will just turn it off and more negative voltage won't make a difference if it is already 0 volts or below. Can someone explain how applying a negative voltage to the base of an NPN transistor causes anything at all to happen within an op-amp.
I am wondering how applying a negative voltage to an op-amp's inputs has any effect on the output at all when both inputs are connected to NPN transistors which require a positive voltage to conduct. A negative voltage will just turn it off and more negative voltage won't make a difference if it is already 0 volts or below. Can someone explain how applying a negative voltage to the base of an NPN transistor causes anything at all to happen within an op-amp.