Information and discussion on high voltage diodes, power supplies, opto-couplers, and more.
Tuesday, May 1, 2012
Diode vs. Rectifier
According to Wikipedia, a rectifier is defined as, ”An electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction. The process is known as rectification. Physically, rectifiers take a number of forms, including vacuum tube diodes, mercury-arc valves, solid-state diodes, silicon-controlled rectifiers and other silicon-based semiconductor switches". 1
Sometimes the term, “rectifier” is used to refer to a discrete diode, and technically, it is correct.
1N6535 Discrete Axial-leaded Diode
At VMI, our terminology varies a bit from Wikipedia’s. It is still correct, but not as common outside the manufacturing environment. The differences in usages probably stems from being a manufacturer of both discrete diodes and diode assemblies, and may have evolved as a kind of verbal short-hand. Now the terms are firmly entrenched throughout the sales, marketing, engineering, production, and QA departments.
SMF6525 Over-molded Diode
Okay, so what’s different? Here at VMI, a diode refers to a discrete device. It can be over-molded with epoxy, as in our K-body diodes (K100S), or SMF6525, or a glass-body type device such as the 1N6535. There are generally two terminations – an anode and a cathode.
The term “rectifier” is short for ‘rectifier assembly’, and is usually constructed using multiple diodes. Rectifier assemblies include high voltage ‘stacks’ (a.k.a. a high voltage stick like the SPJ series), single phase or three phase bridges, doublers, center-taps, and so on. A rectifier assembly generally has multiple diodes, or more than two terminations.
Not to worry though. If you call up and ask for a high voltage rectifier, we’ll know what you mean.