Zener diodes in high frequencies 2

[ssadoglu]

Hi,

Why don't they use zener diodes in high frequencies?

Thanks.

 

[IRstuff]

To do what, exactly?

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize

 

[Skogsgurra]

Don't 'they'? We do,

Of course, that depends what you mean with high frequency.

Gunnar Englund

http://www.gke.org

--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

 

[ssadoglu]

So,I mean ,how it shows a behavior in high-Frequency?

 

[benta]

I think the OP should practise phrasing a coherent question first, including background and parameters.
For instance, what is high frequency in his world?

Benta.

 

[VEBill]

One interpretation of "high frequency" is the formal HF frequency range of 3 to 30 MHz. Same sort of possibly-formal usage as VLF, VHF, UHF, etc. Seems unlikely in this case, but I'll be generous.

About 25 or 30 years ago, I read an article where the author questioned the application of Carl's diode as "protection" in the output power amplifier final stage of low power HF transmitters. His analysis indicated that the relatively high junction capacitance of the zener diode had a larger effect than the Zener or avalanch IV curve.

 

[IRstuff]

Zener diodes are just shy of being full-blown degenerately doped diodes, which means that the junction is heavily doped on both sides. This would tend to make the zener junction capacitance pretty awful for any signal processing usage.

TTFN

FAQ731-376
Chinese prisoner wins Nobel Peace Prize

 

[OperaHouse]

As IR said....I quick grabbed a 10V 1/2W zener and measured 61pF. A generic 1A 400V silicon diode was 30pF.

 

[Skogsgurra]

Was that at 0 V? The capacitance gets lower when reverse biased.

Gunnar Englund

http://www.gke.org

--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.

 

[ssadoglu]

thanks guys for all infos.

 

[MacGyverS2000]

Hmmm, we answered a non-specific question with non-specific answers.

We're getting good at this ;-)

Dan - Owner

http://www.Hi-TecDesigns.com

 

[ssadoglu]

@MacGyverS2000

I got the non-specific my answer that I wanted.

 

[ScottI2R]

I like btruebloods the best. All the diodes I take out to the pub just rattle on and on. I try to speak, they block me out. Truely a one way conversation.

I really am a good egg, I'm just a little scrambled!