Op-Amp Gain Calculator
Calculate the voltage gain of operational amplifier circuits. Determine gain for inverting and non-inverting amplifier configurations.
Voltage Gain
-10.00
Inverting amplifier
Gain in dB: 20.00 dB
How to Use This Calculator
- Select the amplifier configuration: Inverting or Non-Inverting.
- Enter R1 value in ohms (the resistor connected to the input).
- Enter R2 value in ohms (the feedback resistor).
- The calculator displays the voltage gain and gain in decibels (dB).
Op-Amp Gain Formulas
Voltage gain depends on configuration and resistor values:
Non-Inverting: Gain = 1 + R2 / R1
Gain (dB) = 20 × log₁₀(|Gain|)
Example: R1 = 1kΩ, R2 = 10kΩ: Inverting gain = -10 (signal inverted, 10x amplification). Non-inverting gain = 11 (signal in phase, 11x amplification). Gain in dB = 20 × log₁₀(10) = 20 dB.
Full Description
Operational amplifiers (op-amps) are versatile integrated circuits used in countless electronic applications. They can amplify signals, filter frequencies, perform mathematical operations, and much more. Understanding op-amp gain is essential for designing amplifiers, filters, and signal processing circuits.
Op-amps have two basic amplifier configurations: inverting and non-inverting. Inverting amplifiers produce negative gain (signal is inverted), while non-inverting amplifiers produce positive gain (signal is in phase). The gain is determined by the ratio of feedback resistor (R2) to input resistor (R1). Inverting amplifiers use the formula -R2/R1, while non-inverting amplifiers use 1 + R2/R1. Gain is often expressed in decibels (dB) for easier comparison and analysis.
This calculator helps you determine op-amp gain. Select the configuration, enter R1 and R2 values, and it calculates the voltage gain and gain in dB. Use it when designing amplifiers, understanding op-amp circuits, selecting resistor values, or learning about operational amplifiers. Op-amps are fundamental to analog electronics and signal processing.
Frequently Asked Questions
What is an operational amplifier?
An operational amplifier (op-amp) is a high-gain voltage amplifier with differential inputs. It's one of the most versatile integrated circuits, used in amplifiers, filters, oscillators, comparators, and many other circuits. Op-amps have very high input impedance and very low output impedance.
What's the difference between inverting and non-inverting?
Inverting amplifier: Output is inverted (180° phase shift), gain = -R2/R1 (negative). Input signal goes to inverting input (-). Non-inverting amplifier: Output is in phase, gain = 1 + R2/R1 (positive). Input signal goes to non-inverting input (+).
How do I calculate op-amp gain?
Inverting: Gain = -R2/R1 (negative gain, signal inverted). Non-inverting: Gain = 1 + R2/R1 (positive gain, signal in phase). For example, R1=1kΩ, R2=10kΩ: Inverting gain = -10, Non-inverting gain = 11.
What are common op-amp gain values?
Common gains: Unity (1x), 10x, 100x, 1000x. Gain depends on R2/R1 ratio. Higher R2/R1 = higher gain. Very high gains (>1000) may require special considerations for stability and bandwidth. Typical values: R1=1kΩ-10kΩ, R2=10kΩ-100kΩ.