Minimum Slew Rate of Op-Amp

What is Slew Rate?

Slew rate is the maximum rate of change of output voltage of an op-amp.

SR = dV / dt (V/μs)

Minimum Slew Rate Formula

To avoid distortion:

SR_min = 2π f V_peak

• f = frequency of signal
• V_peak = peak output voltage

Why This Matters

• If slew rate is too low, output cannot follow input
• Signal becomes distorted (triangular instead of sine)

Example

Given:

• f = 20 kHz
• V_peak = 10 V

SR_min = 2π × 20000 × 10 ≈ 1.26 V/μs

Required slew rate ≥ 1.26 V/μs

Typical Values

• General-purpose op-amp (LM741): ~0.5 V/μs
• Audio op-amps: 5–20 V/μs
• High-speed op-amps: 100+ V/μs

Summary

The minimum slew rate depends on signal frequency and amplitude. It must be greater than SRmin to avoid distortion.