Please enter valid positive numbers for both fields.
Minimum Slew Rate:0.00 V/µs
Raw Calculation:0 V/s
function calculateSlewRate() {
// Clear previous error
var errorDiv = document.getElementById("srErrorMessage");
var resultDiv = document.getElementById("srResult");
errorDiv.style.display = "none";
resultDiv.style.display = "none";
// Get Inputs
var freqInput = document.getElementById("srFrequency").value;
var freqUnit = document.getElementById("srFreqUnit").value;
var voltageInput = document.getElementById("srVoltage").value;
// Validation
if (freqInput === "" || voltageInput === "" || isNaN(freqInput) || isNaN(voltageInput)) {
errorDiv.innerText = "Please enter valid numerical values.";
errorDiv.style.display = "block";
return;
}
var freq = parseFloat(freqInput);
var volts = parseFloat(voltageInput);
var multiplier = parseFloat(freqUnit);
if (freq <= 0 || volts divide by 1,000,000
var slewRateVus = slewRateVps / 1000000;
// Update UI
document.getElementById("srValueMicro").innerText = slewRateVus.toFixed(4) + " V/µs";
document.getElementById("srValueRaw").innerText = slewRateVps.toLocaleString('en-US', {maximumFractionDigits: 0}) + " V/s";
resultDiv.style.display = "block";
}
Understanding Op Amp Slew Rate
The slew rate of an Operational Amplifier (Op Amp) is a critical specification that defines the maximum rate of change of the output voltage per unit of time. It essentially measures how fast the op amp can respond to a rapidly changing input signal.
If an input signal changes faster than the op amp's slew rate, the output will not be able to keep up, resulting in signal distortion. This is particularly important for high-frequency signals or signals with steep edges, such as square waves.
The Slew Rate Formula
To determine the minimum slew rate required to reproduce a sinusoidal signal without distortion, we use the following mathematical relationship derived from the derivative of a sine wave:
SR = 2 · π · f · Vpeak
Where:
SR: Slew Rate (typically measured in Volts per microsecond, V/µs).
f: The maximum frequency of the signal (in Hertz).
Vpeak: The peak voltage amplitude of the output signal (in Volts).
Why is Slew Rate Important?
Failing to select an op amp with a sufficient slew rate can lead to slew-induced distortion. Instead of a clean sine wave, the output will appear triangular as the amplifier struggles to reach the peak voltage in the required time. This effectively limits the "Full Power Bandwidth" of the device.
How to Use This Calculator
Enter Frequency: Input the highest frequency component of your signal. Use the dropdown to select Hz, kHz, or MHz.
Enter Peak Voltage: Input the maximum peak voltage amplitude (Vp) expected at the output. Note that if you are using peak-to-peak voltage (Vpp), divide that number by 2 to get Vp.
Calculate: Click the button to find the minimum Slew Rate required for your application.
Example Calculation
Imagine you are designing an audio pre-amplifier circuit. You need to handle a signal with a frequency of 20 kHz and a peak output swing of 10 Volts.