Inverting Op Amp Output Voltage Formula

Inverting Op-Amp Formula:

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

Output Voltage (V_out):

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1. What is the Inverting Op-Amp Output Voltage Formula?

The inverting operational amplifier (op-amp) configuration produces an output voltage that is inverted and amplified relative to the input voltage. The gain is determined by the ratio of feedback resistance to input resistance.

2. How Does the Calculator Work?

The calculator uses the inverting op-amp formula:

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

Where:

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

Explanation: The negative sign indicates phase inversion (180° phase shift), while the ratio \( R_f/R_{in} \) determines the voltage gain magnitude.

3. Importance of Inverting Op-Amp Calculation

Details: Accurate calculation of op-amp output voltage is crucial for designing amplifiers, filters, signal conditioning circuits, and various analog electronic systems.

4. Using the Calculator

Tips: Enter feedback resistance and input resistance in ohms (Ω), and input voltage in volts (V). All resistance values must be positive and non-zero.

5. Frequently Asked Questions (FAQ)

Q1: Why is there a negative sign in the formula?
A: The negative sign indicates that the output signal is inverted (180° phase shift) relative to the input signal.

Q2: What is the typical range for resistor values?
A: Resistor values typically range from 1kΩ to 1MΩ, depending on the application and desired gain.

Q3: Can this formula be used for AC signals?
A: Yes, the formula applies to both DC and AC signals, though for AC signals it represents the magnitude gain.

Q4: What are the limitations of this formula?
A: This assumes ideal op-amp characteristics (infinite input impedance, zero output impedance, infinite gain). Real op-amps have limitations that may affect performance.

Q5: How does input impedance affect the circuit?
A: In the inverting configuration, the input impedance is approximately equal to R_in, which should be considered when designing for specific applications.