Open-loop gain

The open-loop gain of an electronic amplifier is the gain obtained when no overall feedback is used in the circuit.

The open-loop gain of many electronic amplifiers is exceedingly high (by design) – an ideal operational amplifier (op-amp) has infinite open-loop gain. Typically an op-amp may have a maximal open-loop gain of around ${\displaystyle 10^{5}}$, or 100 dB. An op-amp with a large open-loop gain offers high precision when used as an inverting amplifier.

Normally, negative feedback is applied around an amplifier with high open-loop gain, to reduce the gain of the complete circuit to a desired value.