What is the output voltage of op amp in open loop configuration when voltage in inverting input is greater than the one in the non-inverting input?
Is there a technical term for this output voltage?
Do datasheets refer to it?
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\$\begingroup\$ Well, the output will be either the high rail voltage or the low rail voltage because that's what open loop op amps do. Suppose you ground the inverting input for a moment and the non inverting one is positive. Now what happens? Then flip it and what happens? \$\endgroup\$– zeta-bandNov 16, 2018 at 19:01
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What is the output voltage of op amp in open loop configuration when voltage in inverting input is greater than the one in the non-inverting input?
The output will swing as far negative as it can go.
Is there a technical term for this output voltage?
Saturation voltage.
Do datasheets refer to it?
Yes. Maximum and minimum output voltage. With common op-amps this is 1 to 3 V from the supply rail. For "rail-to-rail" op-amps it can be close to zero at low currents.
answered Nov 16, 2018 at 19:09
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\$\begingroup\$ And if there is a single positive power supply and the input differential signal Vin+ - Vin- is smaller than 0, is it possible to predict the output voltage? I have just set up a light sensor with an LDR and a LM358 op amp acting as a comparator. I think the circuit I made in the breadboard is successful but when fiddling with a potentiometer, I noticed that a small differential differential input of -0.23V sometimes causes the output to go high and sometimes to go low. I want to be able to mathematically simulate the circuit behaviour for an open educational resource. Any ideas? \$\endgroup\$ Nov 17, 2018 at 15:37
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\$\begingroup\$ I think you need to ask another question. Include a schematic. If this question has not been answered satisfactorily then perhaps an edit is required. \$\endgroup\$ Nov 17, 2018 at 15:43