Re: Low voltage zener diodes

Am 08.10.24 um 11:24 schrieb Pimpom:

When I tested some low voltage zener diodes (<<5V) 30-40 years ago, I found that they didn't have even a reasonably sharp knee, behaving more like LEDs in forward mode, maybe worse. Do I remember correctly? Are they still the same?

yes, that's true. At > 5V they are really avalanche diodes. Around 5-7V
it is a mix. Zeners & avalanche diodes have a different TC, and it
compensates at around 6V.
You can see the onset of avalanche behavior in the noise spectrum with
rising voltage. True Zeners are much better here. For the BZX84 family:
< https://www.flickr.com/photos/137684711@N07/24411798996/in/album-72157662535945536    >
Prof. Zener even sued the industry not to use his name for avalanche
thingies because it was not "his" effect. They settled on Z-Diodes
pretending it was for the V/I curve. But in the end the ghost was out of the bottle.
Gerhard