Editing Rectifier (section)

== Rectifier voltage drop ==
See also: {{Slink|Diode|Forward threshold voltage for various semiconductors}}

A real rectifier characteristically drops part of the input voltage (a [[voltage drop]], for silicon devices, of typically 0.7 volts plus an equivalent resistance, in general non-linear)—and at high frequencies, distorts waveforms in other ways. Unlike an ideal rectifier, it dissipates some power.

An aspect of most rectification is a loss from the peak input voltage to the peak output voltage, caused by the built-in voltage drop across the diodes (around 0.7 V for ordinary silicon [[p–n junction]] diodes and 0.3 V for [[Schottky diode]]s). Half-wave rectification and full-wave rectification using a center-tapped secondary produces a peak voltage loss of one diode drop. Bridge rectification has a loss of two diode drops. This reduces output voltage, and limits the available output voltage if a very low alternating voltage must be rectified. As the diodes do not conduct below this voltage, the circuit only passes current through for a portion of each half-cycle, causing short segments of zero voltage (where instantaneous input voltage is below one or two diode drops) to appear between each "hump".

Peak loss is very important for low voltage rectifiers (for example, 12&nbsp;V or less) but is insignificant in high-voltage applications such as HVDC power transmission systems.