Table of Contents
Operational amplifiers are widely used in electronic circuits for signal amplification. Calculating the gain of these circuits is essential for designing and analyzing their performance. This guide provides a clear, step-by-step process to determine the gain in various operational amplifier configurations.
Understanding Operational Amplifier Basics
An operational amplifier (op-amp) is a high-gain voltage amplifier with differential inputs. The gain of an op-amp circuit depends on the external resistors connected around it. Common configurations include inverting, non-inverting, and differential setups.
Calculating Gain in Inverting Amplifier Circuits
In an inverting amplifier, the input signal is applied to the inverting input through a resistor, and a feedback resistor connects the output to the inverting input. The non-inverting input is grounded.
The voltage gain (Av) is calculated using the formula:
Av = – Rf / Rin
Where Rf is the feedback resistor and Rin is the input resistor.
Calculating Gain in Non-Inverting Amplifier Circuits
In a non-inverting amplifier, the input signal is applied to the non-inverting input. The feedback resistor connects the output to the inverting input, which is also connected to ground through another resistor.
The voltage gain is given by:
Av = 1 + (Rf / Rin)
Summary of Gain Formulas
- Inverting amplifier: Av = – Rf / Rin
- Non-inverting amplifier: Av = 1 + (Rf / Rin)