From: motsteve@attbi.com (carltons)
Newsgroups: sci.electronics.design
Subject: Re: 1.6V zener diodes?
Message-ID:
References: <8a7lquk6hpgjtrqklsiuogten07ifsm7el@4ax.com> <3dab3391$0$11212$1b62eedf@news.euronet.nl> <10Pq9.508$Vv3.7294@newsfep1-gui.server.ntli.net> <3dac83e9$0$3729$edfadb0f@dspool01.news.tele.dk> <3200347.0210161003.18176147@posting.google.com>
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NNTP-Posting-Date: Thu, 17 Oct 2002 08:30:28 GMT
Date: Thu, 17 Oct 2002 08:30:28 GMT
In article <3200347.0210161003.18176147@posting.google.com>, k7itm@aol.com
(Tom Bruhns) wrote:
> motsteve@attbi.com (carltons) wrote in message
news:...
> ...
> > All of the suggestions other than the use of a zener of any sort sound
> > good to me. A Zener is okay for ESD protection as a last resort, but
> > other than that, it has gone the way of the 6AL5 tube diode. Oh yeah! I
> > almost forgot. They make dandy wideband noise sources. BTW, I'm using
> > the term zener loosely. I'm including the diodes rated above 5.6v, which
> > are technically avalanche diodes.
>
> I'd say you're under-rating the zener's usefulness for things other
> than ESD protection and noise generation (and perhaps even over-rating
> it for those). There are some things they do very well for low cost
> which would be quite difficult to do other ways. ;-) (Though we
> haven't seen any confirmation from the OP, his application is likely
> not one of the good ones, of course!)
>
> Cheers,
> Tom
Tom,
Coming from the world of low voltage portable equipment, I'm not a big fan
of shunt regulation. There are also many ways to get better performance
these days. Why use a zener? When I was doing ic design, suggesting a
zener would have gotten you walked out the door immediately. Also, zeners
have really lousy junction capacitance which made them perfect for esd on
portable radios as they didn't rectify the rf past about 1 MHz. All our
radios were 30 MHz and above.
Steve