The limit does not depend on applied voltage. I´m quite experienced with signal processing, measurements and so on, but I don´t know a general definition when distorted a square wave is considered to be 'no square wave' anymore. With square waves this is more difficult, since - due to the overtones the - shape depemds on the attenuation of each overtone (individually) and additionally on the phase shift. There is no (meaningful) frequency with zero output. but attenuated (more and more with rising frequency). So a 1kHz LPF still will have 2kHZ, 10kHz, 100kHz at it´s output. How do you define this limit?įor a sine it´s more simple: You usually do this by the attenuation.įor a 1st order low pass filter fc is defined when the amplitude drops to 71% (-3dB) of of input amplitude. But still you did not define the 'maximum'. The output shape will differ from a clean square wave.

So in a (upper) frequency limited system, the overtones become more attenuated than the fundamental. Now square wave consists of the fundamental frequency plus it´s overtones. But if you define 'square wave' that´s O.K., too.

Click to expand.Unless otherwise stated, when we talk about frequency limits we talk about sine waveform.

Hyperlynx cost