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Op amp basics

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Zero999:
If you built his circuit in real life, it would probably not give exactly the same results. The current limit of an op-amp is not a a tightly controlled parameter. It's just there to protect the output from short circuits which can be handy for interfacing with external circuitry or using another circuit to pull the output to zero, thus disabling it.

For example, look at the short circuit current specification for the NE5532, a common general purpose op-amp. It's typically 38mA, but could be as low as 10mA, or as high as 60mA. In fact if you tried building this circuit with the NE5532 and there was nothing to limit the current from the 1V power supply (a series resistor for example) the op-amp would be destroyed. The NE5532 has diode connected transistors connected back-to-back between its inverting and non-inverting inputs, which would burn out, probably damaging the rest of the op-amp IC, if they were connected directly to a low impedance 1V source.

Refer to the internal schematic on page 7 of the datasheet paying attention to the +IN and -IN inputs. There are two transistors, each with their base and collector junctions connected. They simply act as diodes which limit the voltage between the two inputs to under 0.6V. This is done to protect the next pair of transistors, a differential pair, from having reverse voltages applied between their base and emitter junctions. The diodes don't conduct in normal operation, as the two inputs should theoretically be at the same voltage.
https://www.ti.com/lit/ds/symlink/ne5532a.pdf

This is just one of many ways real life components can differ from simplified simulator models.

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