本文探讨了运算放大器的SlewRate概念，它是输出电路能产生的最大电压变化速率。SlewRate与带宽和Iq的关系中，非线性效应如超出SlewRate导致输出信号形状改变，从而产生失真。
1. Definition
Slew rate is the maximum rate of voltage change that can be generated by the op-amp’s output circuitry. It is measured as voltage relative to time, and the typical unit used in datasheets is volts per microsecond (V/µs).
2. Slew Rate vs. Bandwidth
Poles in the op-amp’s transfer function lead to typical low-pass-filter behavior; signal amplitude decreases as frequency increases, and phase shift occurs. But these effects are linear, and consequently they do not introduce distortion into the output signal.
Slewing, on the other hand, is a nonlinear effect. If a sinusoidal input signal multiplied by the gain of the op-amp results in a slope that is higher than the op-amp’s slew rate, a portion of the output waveform will be a straight line rather than a curving section of a sinusoid. Thus, slewing can modify the shape of a signal and is, therefore, a source of distortion rather than mere modifications of amplitude or phase.
3. Slew Rate vs. Iq
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