A clamper adds a positive or negative DC component to an AC signal, pushing the entire waveform above or below a reference voltage without changing its shape. It typically uses a capacitor, a diode, and a resistor to hold the signal at the desired baseline. Engineers use them to restore DC levels in video signals or to protect inputs from negative voltage swings.
Heard on the job
Check the diode in the clamper if the video sync pulse is floating below ground.
Insider tip
A leaky capacitor will ruin a clamper circuit by letting the DC baseline drift back toward zero over time.
Also heard as
- DC restorer
Do not mix it up with
- Clipper: A clamper shifts the whole waveform up or down, whereas a clipper cuts off the top or bottom of the waveform.