Inverting Op Amp Calculator

Inverting Op Amp Formula:

\[ V_{out} = - \left( \frac{R_f}{R_{in}} \right) \times V_{in} \]

Output Voltage (Vout):

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1. What is an Inverting Op Amp?

An inverting operational amplifier (op amp) is a configuration where the output signal is 180° out of phase with the input signal. It provides amplification with a gain determined by the ratio of feedback resistor (Rf) to input resistor (Rin).

2. How Does the Calculator Work?

The calculator uses the inverting op amp equation:

\[ V_{out} = - \left( \frac{R_f}{R_{in}} \right) \times V_{in} \]

Where:

\( V_{out} \) — Output voltage (V)
\( R_f \) — Feedback resistor (ohms)
\( R_{in} \) — Input resistor (ohms)
\( V_{in} \) — Input voltage (V)

Explanation: The negative sign indicates phase inversion. The gain is determined by the ratio of Rf to Rin.

3. Importance of Inverting Amplifier

Details: Inverting amplifiers are fundamental in analog electronics for signal processing, filtering, and mathematical operations. They provide precise control over gain and are widely used in audio equipment, instrumentation, and control systems.

4. Using the Calculator

Tips: Enter resistor values in ohms and input voltage in volts. All values must be valid (resistors > 0). The calculator will compute the output voltage including the phase inversion.

5. Frequently Asked Questions (FAQ)

Q1: Why does the output invert the signal?
A: The configuration causes the output to be 180° out of phase with the input, which is represented mathematically by the negative sign in the equation.

Q2: What are typical resistor values?
A: Common values range from 1kΩ to 100kΩ, but the exact values depend on the required gain and application constraints.

Q3: Can the gain be less than 1?
A: Yes, when Rf is smaller than Rin, the amplifier actually attenuates the signal (gain < 1).

Q4: What are the limitations?
A: The output cannot exceed the op amp's supply voltage. Also, very high gains may lead to instability or noise issues.

Q5: What about non-ideal op amps?
A: This calculator assumes an ideal op amp (infinite gain, infinite input impedance, zero output impedance). Real op amps have limitations that may affect performance.