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Topic: Zener Diode not Zenering at all ;-( ... (Read 2 times) previous topic - next topic

SirNickity

Some of the replies here seem a little harsh.  Certainly there's a misunderstanding on how zeners work, but honestly I've been there too.  Many of the introductory tutorials sort of paint a zener as a cheap and easy regulator, with very little mention of gradual knees and current dependence.  I had a sense that nothing in life is ever that simple, so there must be more to it.  Turns out there is.  Between "This is what a zener diode looks like" and the graphs in the latter pages of a datasheet, there's quite a void.  The information is there, you just have to know to look for it.

So, it seems to me if you're going to take the time to post a reply criticizing someone's lack of understanding, at least take the time to suggest a correct approach.  If you can't be bothered, just move on.  Thanks to everyone here that takes that extra step, though.  I for one appreciate it greatly.

oric_dan

#21
Jan 08, 2013, 11:30 pm Last Edit: Jan 08, 2013, 11:32 pm by oric_dan(333) Reason: 1
You can see here that transzorbs go all the way down to 3.3V.

http://www.digikey.com/scripts/dksearch/dksus.dll?vendor=0&keywords=transzorb

Download the datasheet, and read up. As already mentioned, they work similar to a
low-inductance, fast-acting zener, and the low-voltage devices are made specifically
for absorbing transients on data lines.

http://www.digikey.com/product-detail/en/SA5.0A-E3%2F54/SA5.0A-E3%2F54GICT-ND/2880343

DROBNJAK

#22
Jan 09, 2013, 03:33 pm Last Edit: Jan 09, 2013, 03:37 pm by DROBNJAK Reason: 1

Some of the replies here seem a little harsh.  Certainly there's a misunderstanding on how zeners work, but honestly I've been there too.  Many of the introductory tutorials sort of paint a zener as a cheap and easy regulator, with very little mention of gradual knees and current dependence.  I had a sense that nothing in life is ever that simple, so there must be more to it.  Turns out there is.  Between "This is what a zener diode looks like" and the graphs in the latter pages of a datasheet, there's quite a void.  The information is there, you just have to know to look for it.

So, it seems to me if you're going to take the time to post a reply criticizing someone's lack of understanding, at least take the time to suggest a correct approach.  If you can't be bothered, just move on.  Thanks to everyone here that takes that extra step, though.  I for one appreciate it greatly.


@SirNickity: Thanks. The original purpose of this forum is for newbies to ask questions. Even if one knows answer to some questions, there is no room for arrogance, because he/she doesn't know the answer to all the questions in the universe.

Googling around doesn't always answer the questions, particularly if one is only guessing what is the right jargon to use.

DROBNJAK


There is this tutorial by Grumpy Mike:

http://www.thebox.myzen.co.uk/Tutorial/Protection.html

I don't know if his previous comments detract from this?


@lemming: pure gold! Thanks for that.

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