Understanding Zener Diodes & when they are not Zener diodes

In this video I describe what a Zener diode is - how they work and where and how they can be used. I also answer the question about when a Zener diode may not be a Zener diode - find out the answer in the video. I also give some tips about using Zener diodes or voltage reference diodes in electronic circuit designs so you can understand all you need to know about Zener diodes.
Zener diodes are very useful devices which are used all over the electronics industry and one of the most common uses in electronic circuits is to provide a stable reference voltage for power lines in various equipment and power supplies.
The circuit symbol is similar to that of a diode but has extra elements to the bar in the symbol to distinguish it from other forms of diode.
It's necessary to understand that a Zener diode has the same forward voltage characteristic as other PN junction diodes, but in the reverse direction the breakdown voltage is well defined, enabling it to be used as a voltage reference.
The Zener diode or voltage reference diode is most commonly used in power supplies or voltage regulators - the simplest circuit is a simple Zener-resistor shunt regulator, but other circuits can used emitter or source followers, etc and others have feedback and allow the output voltage to be adjusted while using the Zener voltage as a reference voltage.
More information so you can understand about Zener reference voltage diodes can be found at: www.electronics-notes.com/art...
Information about the theory of operation and breakdown mechanisms:
www.electronics-notes.com/art...
Information about linear voltage regulators including some Zener diode circuits: www.electronics-notes.com/art...
Website homepage: www.electronics-notes.com
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[@mikestokes235]

Thank you Ian

[@ElectronicsNotes]

Really glad you liked the video. I am planning a few more like it. I’ve a number of ideas in planning, but if you have any requests for more compost to cover, I would love to hear about them. No promises as I need to be very familiar with them before I attempt a vid.

[@Pilot_engineer_19]

When using these devices care should be taken especially around the "knee" on the curve of the device. It can vary quite a bit.

[@ElectronicsNotes]

I agree, it’s necessary to ensure that sufficient current flows through the device to keep it away from the knee point.

[@Meme1man]

❤

[@ElectronicsNotes]

Thanks.

[@Meme1man]

@@ElectronicsNotes ❤️

[@ElectronicsNotes]

@@Meme1man Thanks - glad you liked it.

[@SlyerFox666]

Nice, can you use a resistor to help dissapate the power if the zener is not rated high enough ?

[@ElectronicsNotes]

Typically a resistor is used as a series current limiter / constant current device as shown in the video. The Zener diode has a fixed voltage across it and the current flowing through it is determined by the series resistor and the load.
Often an emitter follower circuit is used if a higher current capacity is needed. There was an example of this in the video. Hope this helps.

[@SlyerFox666]

​​@@ElectronicsNotesYes, I think that helps, so you can use the series resistor to limit current flowing to the zener and as it has it's own internal resistance it has it's own volt drop so it must be able to dissipate the power for that but the series resistor will also limit the current to the load so that's when the emitter follower is used. 👍