Talk:Thyristor

message: GE called them "SCRs" for Silicon Controlled Rectifiers. --Wtshymanski 15:17, 11 May 2005 (UTC)
thread_title: Anything to say about thyristors?

message: photothyristors ???  —Preceding unsigned comment added by 62.180.229.222 (talk) 08:37, 27 May 2009 (UTC)
thread_title: photothyristors

message: The thyristor entry asks whether the thyristor entry and the Silicon Controlled Rectifier should be combined.  I recommend against this.  The thyristor is a broad classification of semiconductor devices, of which the Silicon Controlled Rectifier is but one.  Others are listed in the thyristor entry and include Gate Turn-Off Thyristors (GTOs), MOS Controlled Thyristors (MCTs), Static Induction Thryistors (SITh), among others.  It would be better to link the thyristor entry to these other entries, but describe each individually.
:I agree with the above entry. Thyristors include many different devices. The solution is to expand the thyristor article. I'll offer updates in the coming months. Mak17f 17:16, 1 January 2006 (UTC
yeah keep them seperate
: Could we move all the details about SCRs out of the thyristor article, into the silicon-controlled rectifier article, and leave behind a Wikipedia:Summary style summary of SCRs? --68.0.124.33 (talk) 02:19, 19 August 2009 (UTC)
thread_title:  merge 

message: is an scr apart of thyristor. —The preceding unsigned comment was added by 210.211.225.167 (talk • contribs).
:An SCR is one of the most-common types of thyristor. TRIACs and DIACs are two other very-common types.
:Atlant 11:45, 26 March 2007 (UTC)
thread_title:  SCR? 

message: Why does this page only rate mid-importance in the Electronics Project?  I have only a casual interest in electrical engineering, but I see references to these gadgets in vastly many contexts.  Don't they deserve "high importance", and a really first-rate article?
Ambrose H. Field 18:07, 6 September 2007 (UTC)
replies: text: According to the importance scale, high importance would be appropriate only if the thyristor is "well-known to a reader with casual electronic knowledge". I don't think that's the case. Foobaz·o< 18:18, 6 September 2007 (UTC)
replies: text: All sorts of electronic photographic strobes used to be called "thyristor flashes". I bet lots of people know the term "thyristor" from this application. No mention of photoflashes in the article though. Whogue 07:19, 18 October 2007 (UTC)
thread_title: Status of article

message: the recent demise of mr spira & my reading about his works led me directly to this page about the thyristor, & yet- curiously- neither he nor his uses of the thyristor (if indeed it's the same device) are mentioned.
not being an expert on semiconductor developmental history (I know shockley's name & that's about it!) I'll defer to someone else to deal with this, but it needs dealing with.
http://en.wikipedia.org/wiki/Joel_Spira_%28businessman%29
duncanrmi (talk) 21:31, 18 April 2015 (UTC)
thread_title:  joel spira, dimming device for electric lighting 

message: Hello fellow Wikipedians,
I have just added archive links to  on Thyristor. Please take a moment to review my edit. If necessary, add  after the link to keep me from modifying it. Alternatively, you can add  to keep me off the page altogether. I made the following changes:
*Added archive https://web.archive.org/20090122071434/http://www.abb.com:80/cawp/gad02181/c1256d71001e0037c12568320068995e.aspx to http://www.abb.com/cawp/gad02181/c1256d71001e0037c12568320068995e.aspx
*Added archive https://web.archive.org/20090910162625/http://kn.theiet.org:80/magazine/issues/0809/high-power.cfm to http://kn.theiet.org/magazine/issues/0809/high-power.cfm
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Cheers. —cyberbot IITalk to my owner:Online 02:05, 17 October 2015 (UTC)
thread_title:  External links modified 

message: Hello fellow Wikipedians,
I have just added archive links to  on Thyristor. Please take a moment to review my edit. If necessary, add  after the link to keep me from modifying it. Alternatively, you can add  to keep me off the page altogether. I made the following changes:
*Added archive https://web.archive.org/20120905132123/http://home.roadrunner.com/~mathematikos/Etymology/thyristor.pdf to http://home.roadrunner.com/~mathematikos/Etymology/thyristor.pdf
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Cheers.—cyberbot IITalk to my owner:Online 22:14, 4 January 2016 (UTC)
thread_title:  External links modified 

message: Hello fellow Wikipedians,
I have just added archive links to  on Thyristor. Please take a moment to review my edit. If necessary, add  after the link to keep me from modifying it. Alternatively, you can add  to keep me off the page altogether. I made the following changes:
*Added archive http://web.archive.org/web/20160102202735/http://www.semikron.com/skcompub/en/application_manual-193.htm to http://www.semikron.com/skcompub/en/application_manual-193.htm
*Added archive http://web.archive.org/web/20160104221350/http://membres.lycos.fr/tsetclichy/thyratmel.html to http://membres.lycos.fr/tsetclichy/thyratmel.html
*Added archive http://web.archive.org/web/20151017020524/http://www.st.com/stonline/products/families/thyristors_acswitch/thyristors.htm to http://www.st.com/stonline/products/families/thyristors_acswitch/thyristors.htm
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Cheers.—cyberbot IITalk to my owner:Online 01:12, 28 February 2016 (UTC)
thread_title:  External links modified 

message: Hello Wikipedians,
I'm definitely not a Wikipedian, so a Wikipedian will have fix the "File:Thyristor I-V diagram.svg" as it incorrectly shows the IL being lower than IH. 
Definition: The latching current (IL) of a TRIAC is the minimum value of the load current (current flowing between the cathode and anode) that keeps the device conducting when the gate current (IG) is reduced to zero.Application note 303 - Thyristors and TRIACs: latching current, STMicroelectronics, AN301 (Doc ID 3654) Rev 3, 10 pages, April 2009 
Definition: The holding current (IH) of a TRIAC is the minimum value of the load current (current flowing between the cathode and anode) that keeps the device conducting when the gate current (IG) is zero.Application note 301 - Thyristors and TRIACs: holding current - an important parameter, STMicroelectronics, AN301 Rev 3, 13 pages, March 2008
After the IG triggers the thyristor, the current (I) must increase higher than IL before IG can be lowered to zero, otherwise the thyristor will turn off. 
If I > IL and IG = 0 so the thyristor is latched on, then if I is reduced so I > IH then the thyristor will still remain latched, else if I is reduced further so I < IH then the thyristor will turn off (i.e., I = 0). 
Thus, in the drawing, the IL and IH labels should be swapped, and the VH label should be changed to VL. 
Also, the text in the Thyristor page should be changed accordingly. 
207.107.66.194 (talk) 21:31, 26 March 2016 (UTC)
thread_title:  Changes Required 

message: Surely: Junction J2 never conducts by avalanche breakdown. In the forward conducting mode conduction across J2 is due to holes that originate in the anode heavily roped p-region and have travelled as minority carries across the lightly doped n-region, and elections that originated in the heavily doped cathode n-region and have travelled across the moderately doped p-region, just as the two transistor model suggests; the n and p layers in the middle of the sandwich are much thicker than a transistor base but they still function by conducting minority carriers. The mathematics modelling of Thyristors in “Introduction to Semiconductor Materials and Devices”, M.S. Tyagi, Wiley 1988 makes it clear that the device does operate as two interconnected transistors. Bethyoung1729 (talk) 11:36, 15 June 2019 (UTC)
thread_title:  Erroneous description in “Function of the Gate Terminal” 

message: The introduction section explains that the thyristor can be thought of as two complementary BJTs with the collector of each connected to the base of the other.  Something about this explanation just does not sit right.
With the two transistor model wired as shown, supposing the thing is initially "ON" it seems that pulling the gate voltage negative with respect to the cathode will decisively return the whole system to its "OFF" state.  The NPN base-collector and base-emitter junctions would be reverse biased and almost immediately halt emitter-base and thus emitter-collector conduction of the PNP element.
But the article almost immediately goes on to say that "the thyristor continues to conduct, irrespective of the gate voltage" which seems wholly inconsistent with the prior explanation of a thyristor as two transistors and this inconsistency does not seem helpful for a reader trying to
understand how the latching behaviour of a thyristor actually occurs.
I built some simple circuits up in circuitjs to experiment which I cannot share here because apparently Wikipedia will not let me post any links to falstad.com where the simulator is hosted.  But anyway at least insofar as that simulator models these components the thyristor latches very differently from two transistors.  I may have to order some real parts to try on the bench.
24.53.240.163 (talk) 21:42, 23 June 2020 (UTC)
thread_title:  Something seems off with the explanation 

message: The article reads:
* [...] or (b) the current through the device (anode−cathode) becomes less than the holding current specified by the manufacturer.
Should we note that often there is a max value for IH (hold guaranteed) specified, but not min value (opening is guaranteed)? From a design aspect it is important to go below the min value. IIRC, in cases where both values are given, there were off by a factor of 20 or something. -- Pemu (talk) 12:01, 12 April 2024 (UTC)
thread_title: Going below holding current