Clampers
A clamper is an electronic circuit that produces an output, which is similar to the input but with a shift in the DC level. In other words, the output of a clamper is an exact replica of the input. Hence, the peak to peak amplitude of the output of a clamper will be always equal to that of the input.
Clampers are used to introduce or restore the DC level of input signal at the output. There are two types of op-amp based clampers based on the DC shift of the input.
This section discusses about these two types of clampers in detail.
A positive clamper is a clamper circuit that produces an output in such a way that the input signal gets shifted vertically by a positive DC value.
The circuit diagram of a positive clamper is shown in the following figure −
From the figure above, you can observe that the positive clamper shifts the applied input waveform vertically upward at the output. The amount of shift will depend on the value of the DC reference voltage.
A negative clamper is a clamper circuit that produces an output in such a way that the input signal gets shifted vertically by a negative DC value.
The circuit diagram of negative clamper is shown in the following figure −
We can observe from the output that the negative clamper shifts the applied input waveform vertically downward at the output. The amount of shifting will depend on the value of DC reference voltage.