As active devices go, it doesn’t get much simpler than a diode. Two terminals. Current flows in one direction and not in the other. Simple, right? Well, then there are examples with useful side effects like light emitting diodes. [GreatScott] points out that there are other useful diodes and, in particular, he posted a video covering Schottky and Zener diodes.
These special diodes have particular purposes. A Schottky diode has a very low voltage drop and fast switching speed. Zener diodes have application in simple voltage regulation.
If you ever wondered, these exotic diode names because of their inventors. [Walter Schottky] was a German and although some people call it a hot carrier diode, most people use the inventor’s name. We don’t know of another name for [Clarence Melvin Zener]’s invention.
If you wonder why you care about high speed in a diode, [GreatScott] has a good demo of rectifying a signal with a regular diode and a Schottky. At a certain frequency, the normal diode starts conducting when it should be off at a certain frequency. The Schottky diode is able to turn off faster, so it can handle a much higher frequency.
There are other exotic diodes including PIN diodes, Gunn diodes and more. After the apocalypse, you might want to try making your own with sodium bicarb. Oddly enough, we covered [Afroman]’s video last year that covered similar topics, if you want a second point of view.