A circuit that takes an alternating waveform as input, and produces an output waveform that is either all positive or all negative (depending on which way the rectifier is "facing"). Two types exist, half-wave, and full-wave (also referred to as "bridge"). Taking, for example, rectifiers that are oriented for positive output:
- The half-wave rectifier will simply eliminate the negative portions of the waveform, making those portions zero.
- The full-wave rectifier will change the algebraic sign of the negative portions of the waveform to make them positive.
A simple diode makes a (somewhat imperfect) half-wave rectifier.