Editing Rectifier (section)

=== Voltage-multiplying rectifiers ===
{{Main|Voltage multiplier}}
{{See also|Voltage doubler}}
[[File:Switcheable rectifier.svg|thumb|300px|Switchable full bridge/voltage doubler.]]
The simple half-wave rectifier can be built in two electrical configurations with the diodes pointing in opposite directions, one version connects the negative terminal of the output direct to the AC supply and the other connects the positive terminal of the output direct to the AC supply. By combining both of these with separate output smoothing it is possible to get an output voltage of nearly double the peak AC input voltage. This also provides a tap in the middle, which allows use of such a circuit as a split rail power supply.

A variant of this is to use two capacitors in series for the output smoothing on a bridge rectifier then place a switch between the midpoint of those capacitors and one of the AC input terminals. With the switch open, this circuit acts like a normal bridge rectifier. With the switch closed, it acts like a voltage doubling rectifier. In other words, this makes it easy to derive a voltage of roughly 320&nbsp;V (±15%, approx.) DC from any 120&nbsp;V or 230&nbsp;V mains supply in the world, this can then be fed into a relatively simple [[switched-mode power supply]]. However, for a given desired ripple, the value of both capacitors must be twice the value of the single one required for a normal bridge rectifier; when the switch is closed each one must filter the output of a half-wave rectifier, and when the switch is open the two capacitors are connected in series with an equivalent value of half one of them.

[[File:Cockcroft Walton Voltage multiplier.png|thumb|left|250px|Cockcroft Walton voltage multiplier]] In a [[Cockcroft-Walton voltage multiplier]], stages of capacitors and diodes are cascaded to amplify a low AC voltage to a high DC voltage. These circuits are capable of producing a DC output voltage potential up to about ten times the peak AC input voltage, in practice limited by current capacity and voltage regulation issues. Diode voltage multipliers, frequently used as a trailing boost stage or primary high voltage (HV) source, are used in HV laser power supplies, powering devices such as [[cathode-ray tube]]s (CRT) (like those used in CRT based television, radar and sonar displays), photon amplifying devices found in image intensifying and photo multiplier tubes (PMT), and magnetron based radio frequency (RF) devices used in radar transmitters and microwave ovens. Before the introduction of semiconductor electronics, [[AC/DC receiver design|transformerless vacuum tube receivers]] powered directly from AC power sometimes used voltage doublers to generate roughly 300&nbsp;VDC from a 100–120&nbsp;V power line.