Slew Rate Limit

How to Use This Calculator

The slew rate (SR) is the maximum rate at which an op-amp's output voltage can change, in volts per second — a large-signal limit that is separate from the gain-bandwidth product. A sine wave of amplitude Vpeak at frequency f needs its steepest slope exactly at the zero crossings, where |dV/dt| = 2πf·Vpeak. The calculator therefore answers two equivalent questions. In "Max amplitude at f" mode it computes Vpeak,max = SR / (2πf): the largest sine amplitude the part can reproduce at your frequency without slew distortion. In "Max frequency at Vp" mode it inverts this to fmax = SR / (2π·Vpeak), the full-power bandwidth for your chosen amplitude. Enter the SR from the datasheet (with its unit), plus f and Vpeak, and the result panel shows the limit, a headroom percentage, and a clear OK / slew-limited verdict.

Input fields

Step by step

1. Pick the mode that matches your question: "what's the biggest clean signal at my frequency?" or "how fast can I go at this amplitude?"
2. Enter SR, f and Vpeak. With the defaults — a 741-class part (0.5 V/µs), 10 kHz, 10 V peak — the calculator finds Vpeak,max ≈ 7.96 V: your 10 V requirement exceeds it, so the verdict is slew-limited.
3. Read the headroom: positive means margin (e.g. +20% means you could raise the amplitude or frequency by about that much before slewing); negative means you are over the limit by that fraction.
4. If limited, fix it one of three ways: choose a higher-SR op-amp, reduce the required amplitude (add gain earlier in the chain), or lower the bandwidth requirement. Then re-check with the Bandwidth Analysis calculator — GBW and slew rate are independent budgets that both have to pass.

Two interpretation notes. The 2πf·Vpeak slope is the peak requirement of a sine; other waveforms have their own worst-case slopes (a triangle wave of amplitude V at frequency f needs a constant slope 4fV, and a step needs infinite). And slew limiting is a large-signal effect: small signals well below the limit are governed by GBW instead, which is why a part can pass a 100 mV test at 1 MHz yet fail a 5 V test at 50 kHz.

What It Means in a Real Circuit

The slew rate comes from the op-amp's internal compensation stage: its output current is limited by how fast the internal charge can move, so during fast transients the output follows a straight ramp at ±SR instead of tracking the ideal curve. On a sine wave that shows up as flattened peaks and steeper zero-crossings — the waveform turns into something like a triangle with rounded corners. The distortion is not gentle: once any part of the cycle slews, the output contains odd harmonics well above the fundamental, so "just barely under the limit" still audibly colors an audio signal. Designers therefore keep the required 2πf·Vpeak at or below about half the datasheet SR as a comfortable margin, and even less for parts whose SR degrades with supply voltage or output load.

Slew rate and gain-bandwidth product are different budgets that people often confuse. GBW limits small-signal bandwidth — how much closed-loop gain you have at a given frequency — while SR limits large-signal swing speed regardless of gain. A unity-gain buffer (noise gain 1) using a 1 MHz-GBW, 0.5 V/µs part has small-signal bandwidth near 1 MHz but can only swing ±7.96 V at 10 kHz; push the amplitude to 10 V and it slews even though GBW says "fine". Conversely, a high-SR, low-GBW part may swing fast but cannot amplify wideband signals with gain. Audio design lives in this intersection: full-scale 20 V peak-to-peak (10 V peak) audio to 20 kHz needs SR ≥ 2π·20000·10 ≈ 1.26 V/µs, which a 741 (0.5 V/µs) cannot deliver but a NE5532 (≈9 V/µs) handles with about 7× margin.

In real layouts the effective limit can be worse than the datasheet number in three common ways. First, many parts specify SR at ±15 V supplies; running from lower rails reduces it. Second, heavy capacitive loads force the output stage to charge capacitance with its limited current, adding an extra slew component and sometimes causing ringing or instability — datasheets state a safe load-capacitance range for exactly this reason. Third, temperature shifts the internal biasing, so SR at −40 °C industrial temperature can be well below the 25 °C figure. When your application is near the edge of its requirement, derate against all three: measure (or use the low-temperature spec) rather than trusting the nominal number, and verify with an actual sine sweep on a scope — the flattened peak in the illustration above is the signature you are checking for.