What is the purpose of negative feedback in an op-amp?

Negative feedback in an operational amplifier (op-amp) plays a critical role in stabilizing the gain of the circuit. When negative feedback is applied, a portion of the output voltage is fed back to the inverting input. This feedback effectively reduces the overall gain of the op-amp to a more predictable and stable level.

Without negative feedback, the gain of the op-amp can be very high and can vary significantly with changes in temperature, supply voltage, and other factors. By incorporating negative feedback, the gain becomes mainly determined by external resistor values rather than the intrinsic characteristics of the op-amp itself, leading to less variability and improved linearity in the performance of the amplifier.

This stabilization of gain is essential for applications where consistent performance is required, such as in signal processing, filtering, or amplification circuits, where precision is key. Thus, the primary purpose of negative feedback is to ensure that the amplifier operates within a defined and stable gain range, enhancing the reliability and predictability of its responses to input signals.