Re: Low voltage zener diodes

On a sunny day (Tue, 8 Oct 2024 14:54:39 +0530) it happened Pimpom
<Pimpom@invalid.invalid> wrote in <sT6NO.84691$Xx4a.59580@fx11.ams1>:

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.
These days there  are 'bandgap' references, those are about 1.25V,
extr3mely stable.
 https://en.wikipedia.org/wiki/Bandgap_voltage_reference
You can also use a chip like TL431 (google TL431.pdf)
to make a reference from about 2.5 V upwards
to whatever you like with 2 resistors as voltage devider.
IIRC it uses that bandgap reference principle.
 https://en.wikipedia.org/wiki/TL431#Applications