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Why is the letter "U" used here for the abbreviation of Voltage? According to every book I have on the subject, and the way we were all taught electronics in school in the US, the standard abbreviation is "E" or "V". Why confuse the readers by stepping away from common terminology used in electronics? --Craxd (talk) 13:54, 11 January 2011 (UTC)
Why the cut in voltage is called knee voltage somewhere ? Please answer me. And here it's said , it is zener breakdown the zenner knee voltage.— Preceding unsigned comment added by Hemantshripal (talk • contribs) 03:40, 26 December 2011 (UTC)
"A reverse-biased Zener diode will exhibit a controlled breakdown and allow the current to keep the voltage across the Zener diode at the Zener voltage. For example, a diode with a Zener breakdown voltage of 3.2 V will exhibit a voltage drop of 3.2 V if reverse bias voltage applied across it is more than its Zener voltage."
Uh ? Surely this can be re-worded so as to make sense.
Actually, this is the best explanation I have seen, and that includes the one found in Horowitz & Hill. The current flow increases as the voltage across the diode increases past the diode's Zener voltage, and works to keep the voltage that appears across the diode at a constant. (The Zener voltage is something designed into the diode and is a fixed value for a given diode.) So if you put a voltmeter across the Zener diode and turn up the voltage (in the reverse-bias sense) the voltage shown on the voltmeter will rise to the Zener voltage and then stay there, even as the applied voltage continues to rise.
Charles Antonelli Nov 2009 —Preceding unsigned comment added by 141.211.4.71 (talk) 16:27, 9 November 2009 (UTC)
Re the destruction of a conventional diode, surely the point is the POWER developed in the device. The mode of destruction is overheating. In the case of a broken-down diode the voltage is likely to be quite large, and therefore a relatively small current will develop sufficient power to overheat the device. --Andrew Smith May 2009
How about something like ...
"As the reverse voltage across a Zener diode is increased, it will exhibit a controlled breakdown at its Zener voltage. This will allow the current through it to keep that constant voltage across the diode. For example, a diode with a Zener breakdown voltage of 3.2 V will exhibit a constant voltage drop of 3.2 V across it, if the reverse bias voltage applied across it increases beyond 3.2V." — Preceding unsigned comment added by 121.216.41.170 (talk) 05:21, 12 March 2017 (UTC)
Isn't the schematic symbol in the top right photo for a Schottky diode? I always thought the Zener symbol had the tips at a 45 degree angle.
Hyperlight 00:40, 13 April 2007 (UTC)
A Schottky diode has extra bits on the tips. See Diode for a list of symbols. I have seen zener's shown with angled tips (eg in Bill Orr's "Radio Handbook") but more of the references I have (eg ARRL Handbook, Silicon Chip) use the image shown here. images.google.com also shows a variant with only one side of the cathode bar having a bent tip. I know there are standards but I don't have references to them. --PeterJeremy 09:18, 15 May 2007 (UTC)
In Australia, at any rate, the symbol for a Zener diode is the same as that shown except that the top does not have the right angle tip. Source is Standards Associoation of Australia 1986, SAA Hb3 - Electrical and Electronic Drawing Practice for Students. I believe this is also the standard symbol in the UK. Perhaps there should be a picture of the two (or three) standard forms of drawing the Zener diode symbol along with the region to which they apply. —Preceding unsigned comment added by 124.171.252.31 (talk) 07:16, 7 September 2007 (UTC)
The Schottky should have a "hat" that looks more like a fancy "S" (for Shottky). The Zener should have a hat that looks like a "Z". The "Z" not only stands for Zener, but it looks like the i-v curve. So, the symbol on the page as is now should be flipped (so it looks like a Z). --TedPavlic | talk 00:09, 23 April 2008 (UTC)
The "Zener Diode" page has the symbol: http://en.wikipedia.org/wiki/File:Zener_diode_symbol-2.svg
which is quite different to the Zener symbol on the "Diode" page: http://en.wikipedia.org/wiki/File:Zener_diode_symbol.svg
Please would knowledgeable someone add a correction or note to indicate why there is a difference ? Darkman101 (talk) 09:52, 13 May 2013 (UTC)
IIs the reason that a normal diode "destroys itself" due to avalanche breakdown? If so, then we should say this explicitly. Also, a diode doesn't ever really destroy itself, unless it is connected to a very low resistance path. In this case, a diode can destroy itself in reverse bias as well as forward bias, can it not? So, we should remove this vagueness I think, and be a bit more clear. I can make the changes, I just want to check with the other authors first. I guess I could also check a textbook, but I don't have one with me right at this moment. --User:Dgrant
@ 2006-06-25 13:14Z
What is not clear to me is what happens when a zener is destroyed. Does it go open circuit or closed circuit? One can imagine that it would go open circuit at catasrophic destruction but what about otherwise? — Preceding unsigned comment added by 60.240.180.162 (talk) 13:16, 2 August 2011 (UTC)
I just did the experiment several times with a 15V 500mW Zener, connected directly to a variable voltage PSU. At 14V, no current flows (a DVM shows 0.00 uA, so this is pretty good). As the voltage rises to about 15.8V, the current increases (though the diode gets hotter, which reduces current slightly), then the diode's internals melt. At meltdown, all 6 specimens went short-circuit, rather than open-circuit. This fail-short rather than fail-open is good for protecting the regulated circuit, so it's clearly desirable; is it also a designed behaviour, or was this experiment simply lucky? RichardNeill (talk) 15:32, 26 October 2011 (UTC)
We should also have a diagram to show how Zener breakdown occurs. Without a diagram showing the mechanism and/or the I-V relationship, this article is sadly, fairly useless. I will draw one homemade using Xfig, unless someone beats me to it. --User:Dgrant
we should also have a graph showing the break down voltage and the knee voltage in the V-I relationship [user:shandhir]
There seems to be disagreement on whether Zener is pronounced like "zeener" or "zenner," possibly a British/American distinction. Authoritative comments on this would be helpful. --teejaydub
In all my years, I have only ever heard it pronounced to rhyme with "Warrior Princess" Darkman101 (talk) 06:22, 22 August 2013 (UTC)
I suggest those who knew Clarence at Carnegie Mellon, or his family members, give a definitive answer. — Preceding unsigned comment added by 108.213.76.24 (talk) 15:16, 31 July 2014 (UTC)
This obituary says ZEE-ner. The wording suggests this is the family pronunciation. http://www.nytimes.com/1993/07/06/obituaries/clarence-m-zener-87-physicist-and-professor-at-carnegie-mellon.html — Preceding unsigned comment added by 155.98.69.99 (talk) 01:29, 9 December 2014 (UTC)
"Zener diodes are widely used in electronic circuits." - when else are diodes used? I'm totally deleting that one. Fresheneesz 21:34, 2 February 2006 (UTC)
Most or all of this article was transwikied to wikibooks 18:37, 16 August 2006. Anyone know why? The user (IP only) did not copy the edit history or talk... I'll be happy to do that if there's a reason it was sent over. --SB_Johnny | talk 23:55, 16 August 2006 (UTC)
More information on the Zener Diode Breakdown would be great!!
@ 2006-09-19T17:17Z
"If insufficient current flows through D, then UOUT will be unregulated, and could rise as high as UIN." - could someone provide a reference for this claim. A zener diode can be modelled as a perfect zener diode with a resistor in series and a resistor in parallel. Whilst the output is unregulated at low currents (heavily dependent on the current flow through the diode), the output voltage will always be less than the nominal zener voltage. --PeterJeremy 00:50, 5 December 2006 (UTC)
In view of the lack of comments, I have corrected the statement, adding a reference to the behaviour of Voltage regulator tubes - which do behave as was previously written. --PeterJeremy 09:01, 18 December 2006 (UTC)
I believe that UOUT can in fact rise to as high as UIN. Assume as stated above that a zener diode may be modelled as an ideal zener with a resistor in series (Rs) and another in parallel (Rp). Below the zener voltage this model reduces to a resistor with value Rs+Rp. The voltage UOUT across this resistor will be UIN x (Rs+Rp)/(Rs+Rp+R) where R is the resistor in series with the zener shown in the schematic. This can be as high as UIN for (Rs+Rp) very large relative to R (the usual case).
If there are no comments I will make this change. May 6 2007
In the "usual case", the current through the diode will be in the flattish area above the knee current. To reduce the current through the diode, you need to increase R so (Rs+Rp) will never be very large relative to R. A study of the I/V curve for a zener diode will more clearly show the behaviour but I haven't been able to locate a datasheet with an I/V curve in it. Rummaging around with Google finds and - both of which include typical curves. --PeterJeremy 09:29, 15 May 2007 (UTC)
Rs ≪ R ≪ Rp if you haven't abused your diode. —Ryan 09:23, 9 November 2007 (UTC)
I once saw a thing called a "thyrector" in an old 60's era schematic. I remember it being drawn as ->|<- so I imagine it as being two Zener diodes connected in opposite directions, which would provide A/C voltage regulation. Is this correct? This would make it different from, say, a "diac" which would avalanche above the break voltage. —Preceding unsigned comment added by 66.68.159.105 (talk) 00:47, 10 April 2008 (UTC)
I am also not sure how it works? —Preceding unsigned comment added by 75.182.89.34 (talk) 20:47, 15 February 2009 (UTC)
Other than specifications for a particular zener diode, are there any references that have been used? —Preceding unsigned comment added by 138.64.2.77 (talk) 16:21, 16 July 2008 (UTC)
The article says "Note that because it is almost always the reverse breakdown property of the Zener diode which is useful, in circuit schematics the Zener diodes typically point in the opposite direction of traditional diodes – the arrows point in the opposite direction to the current." 1) I cannot find any examples of this 2) The article shows the normal diagram. So either the diagram is wrong, or this statement is wrong. —Preceding unsigned comment added by 98.218.13.96 (talk) 01:48, 29 December 2008 (UTC)
although there are many customised versions (with as little as 0.03V difference, as seen on Digikey), here are the more common voltages (for quick reference): [2.4V, 2.7V, 3.0V,] 3.3V, 3.9V, 4.3V, 4.7V, 5.1V, 5.6V, 6.2V, 6.8V, 7.5V, 8.2V, 9.1V, 10V, 11V, 12V, 13V, 15V, 16V, 18V, 20V, 24V, 27V, 30V, 33V, 36V, 39V, 47V, 51V, 56V, 62V, 68V, 75V, 82V, 91V, 100V, 110V, 150V, 160V, 180V and 200V. Charlieb000 (talk) 00:13, 4 August 2012 (UTC)
I recently read this page to find out what a zener diode is and how it works but found this page to be unclear on what is considered a zener diode and what is not, as well as on how a zener diode works and how this differs from other diodes that are not considered zeners. Allow me to explain what confused me:
A little reordering of information and consistency in wording might solve a lot of this. The first paragraph should then explain what a zener diode is and, if appropriate, what similar types of diode are not considered zeners and the difference between the two. It should explain what mechanisms are involved and the various terms used to refer to them. Where there are multiple terms for the same thing, this should be explained once and only one of the terms should be used on the rest of the page.
Unfortunately, I was reading this page to find out about zeners, so I am unable to rewrite the page to explain them myself. If somebody can clarify, I might be able to rewrite the page to make it more clear to the uninitialized. — SkyLined (talk) 13:31, 14 February 2013 (UTC)
Please see the corresponding discussion thread at Wikipedia talk:WikiProject Electronics. Thanks! • Sbmeirow • Talk • 23:34, 15 December 2013 (UTC)
I have gone through the article and made the capitalisation of Zener consistently capitalised. I saw that about a year ago the article was made lower case, but this was not done thoroughly and the article remained inconsistent. It is arguable whether the word has yet entered the lexicon as a common noun—books sources seem fairly divided on this. I found a MoS, Science and Technical Writing: A Manual of Style which categorically says "Zener" should be capitalised. In the absence of any better authority, I think we should go with that. SpinningSpark 15:48, 30 March 2014 (UTC)
Neon and Argon bulbs were used as voltage references long before the Zener Diode was invented. It might be useful to add something on these classical parts in the history. --Mccainre (talk) 20:11, 2 January 2015 (UTC)
The article says about very thin (<1 µm) depletion region and field of value 500kV/m at 5V reverse voltage. Obviously it is wrong: 5V/1µm=5MV/m, 10 times more. And an article [Zener effect] referenced here says about 30 MV/m (Zener breakdown voltage is found to occur at electric field intensity of about 3×10^7 V/m), another 6 times more.
It should also be noted that electric field is not uniform in entire depletion region thickness: only PIN diode can have uniform field in the non-doped 'I' region, and the depletion region must contain the non-doped one plus some margins, which holds electric charges necessary to create the field. Along a line of electric field in a PN junction the field is strongest just on a boundary between P and N regions (assuming flat junction geometry and uniform permittivity); for uniform P and N region doping, the field decreases linearly from PN boundary to boundary between depletion region and each of mobile charge regions. This creates a possibility that the field in the PN boundary is strong enough to create electron-hole pairs due to Zener effect, and these electron and/or holes create more carriers due to avalanche effect, rather than creating carriers due to Zener effect in entire volume of the depletion region.
JerzyTarasiuk (talk) 19:36, 10 November 2017 (UTC)
A significant portion of this Wikipedia article and substantially all of this page at Engineers Edge are verbatim copies of each other, including some illustrations. Wikipedia is not citing the latter, and the latter is claiming copyright, all rights reserved, without attribution to Wikipedia. Who is the rightful copyright holder? 24.76.182.33 (talk) 17:55, 2 July 2018 (UTC)
A zener diode is a unique diode that allows current to flow in the forward direction in the same manner as an ideal diode, but will also permit it to flow in the reverse direction when the voltage is above a certain value known as the breakdown voltage, "zener knee voltage" or "zener voltage"
A Zener diode is a particular type of diode that, unlike a normal one, allows current to flow not only from its anode to its cathode, but also in the reverse direction, when the Zener voltage is reached.
A Zener diode is a special kind of diode which allows current to flow in the forward direction same as an ideal diode, but will also permit it to flow in the reverse direction when the voltage is above a certain value known as the breakdown voltage, "Zener knee voltage" or "Zener voltage."
A Zener diode is a ******* **** ** diode ***** allows current to flow in the forward direction ## ### same ###### as an ideal diode, but will also permit it to flow in the reverse direction when the voltage is above a certain value known as the breakdown voltage, "Zener knee voltage" or "Zener voltage."
A Zener diode is a special kind of diode which allows current to flow in the forward direction in the same manner as an ideal diode, but will also permit it to flow in the reverse direction when the voltage is above a certain value known as the breakdown voltage, "Zener knee voltage" or "Zener voltage."
A Zener diode is a ******* **** ** diode ***** allows current to flow in the forward direction in the same manner as an ideal diode, but will also permit it to flow in the reverse direction when the voltage is above a certain value known as the breakdown voltage, "Zener knee voltage" or "Zener voltage."
A Zener diode is a diode which allows current to flow in the forward direction in the same manner as an ideal diode, but will also permit it to flow in the reverse direction when the voltage is above a certain value known as the breakdown voltage, "zener knee voltage" or "zener voltage".
A Zener diode is a ###### diode **** allows current to flow in the forward direction in the same manner as an ideal diode, but will also permit it to flow in the reverse direction when the voltage is above a certain value known as the breakdown voltage, "zener knee voltage" or "zener voltage".
Who invented it? Someone called Zener? When? --Hugh7 (talk) 05:22, 26 June 2019 (UTC)
This sentence is wrong I believe. "The two types of diode are in fact constructed the same way and both effects are present in diodes of this type". The avalanche effect is dominant in lightly doped PN diodes which has fatter depletion regions so there is space for the electrons to really pick up speed. While zener effect occurs in heavily doped PN diodes where the electric field is made stronger in that thin region. reference - harvard — Preceding unsigned comment added by Aditya8795 (talk • contribs) 19:12, 23 August 2019 (UTC)
The voltage (horizontal) scale of this characteristic curve is inconsistent. On the right side, at a particular image size, +0.65V measures 80px from the vertical axis along the horizontal axis. However, on the left side, -17.1V measures 120px. If the scale were consistent, +0.65V would be only about 5px from the vertical axis on the right side (or -17.1 would be, impractically, 2100px). It's been a few decades since I worked with this stuff, so maybe this is common, but I think it looks deceptive to a general audience. A log scale could be used (and shown with markings on the axis). Better, use a lower zener voltage – say, 3.1V; at 0.025 V/px, +0.65V is 26px on the right, and -3.1V is 124px on the left. — Preceding unsigned comment added by AlanM1 (talk • contribs) 19:13, 24 October 2019 (UTC)
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