Hey just look out this clamping circuit and its waveforms:

A CLAMPING CIRCUIT effectively clamps or ties down the upper or lower extremity of a waveform to a fixed dc potential. Clamping does not change the amplitude or shape of the input waveform.



[img]http://www.tpub.com/content/neets/14181/img/14181_214_1.jpg[/img]


[img]http://www.tpub.com/content/neets/14181/img/14181_214_2.jpg[/img]

A POSITIVE CLAMPER will clamp the lower extremity of the input waveform to a dc potential of 0 volts.

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