[[[[[ Varistor ]]]]] or VDR

[1843]

Hi all,

I saw a VDR in a circuit some time ago, but I don't know what they do....?
Could someone explain about them?
What advantages they have?
Is it possible to use two zener diodes (by fasten both kathodes of them together) insead of a VDR???


Best Regards,
1843

[Carl-NC]

Voltage Detector Reset. Basically, it monitors a voltage and if it falls below a threshold the detector triggers an output. In other words, it's a comparator. No, the zeners would not do the same thing.

- Carl

[Reg]

Hi Carl,

I have seen VDR also stand for Voltage Dependent Resistor which is basically a varistor.

Here is a link to some info about them.

http://www.epcos.com/inf/70/db/var_01/00190041.pdf

Reg

[Carl-NC]

Hmmm... OK, also a Video Digital Recorder.

So a VDR looks a lot like a back-to-back zener, but instead of a sharp avalanche it has a more resistive slope.

- Carl

[1843]

Many thanks to Carl and Reg,
Cheers