Frequency Response and Slew Rate Limiting Equipment specifications should reflect the intended use of the equipment. At standard NTSC video signal levels, many video distribution amplifiers, including ours at VAC, are slew rate limited. This means that the upper frequency response increases if a smaller sinusoidal input signal is applied, while it will typically halve for a 2 Vp-p sinusoidal input signal. Additional circuit design factors come into play at smaller input signal levels.
More detailed information is presented in the following.
The highest rate at which a device will change in responding to a change in the input signal. Distortion in the output signal caused by the slew rate of the device being too slow to allow the device to respond properly to a change in the input signal. When reading frequency response specifications, it is also necessary to know at what signal amplitude the given values apply. The reason for this is that often a particular device has a very wide frequency response provided that only very small signals are applied, but slew rate limiting causes a much narrower frequency response when a normal signal is applied. In this instance, if a signal consisting of a 150 MHz sine wave with a peak amplitude of one volt is applied to the device, the output will be seriously distorted due to the slew rate limitation.