what is open loop gain in op amp
Open-loop gain The open-loop gain of an amplifier is the gain obtained when no overall feedback is used in the circuit. Open loop gain, in some amplifiers, can be exceedingly high. An ideal operational amplifier has infinite open-loop gain. Typically an op-amp may have a maximal open-loop gain of around   10 5   {\displaystyle 10^{5}} . The very high open-loop gain of the op-amp allows a wide range of feedback levels to be applied to achieve the desired performance.
Negative feedback Whereas positive feedback tends to lead to instability via exponential growth, oscillation or chaotic behavior, negative feedback generally promotes stability. Negative feedback tends to promote a settling to equilibrium, and reduces the effects of perturbations. Negative feedback loops in which just the right amount of correction is applied with optimum timing can be very stable, accurate, and responsive.