Exploring Op Amp Loading

Op amps are generally pretty easy to apply, but there are some practical nonideal behaviors you have to keep in mind. [EEforEveryone] takes a test board with some 2X amplifiers on it and — after some fiddling around with the scope probes — demonstrates the effect of capacitive loading on the output of an op amp. (Video, embedded below.)

The op amp in question is the OP07. In fact, there are two identical opamps looking at the single input. The output of one op amp feeds directly to the scope probes. The second one passes through a bipolar transistor buffer consisting of an NPN and PNP transistor. Both outputs have optional capacitors that can be jumpered in or out of the circuit.

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