Talk:Silicon controlled rectifier

Inventor: Gordon and Robert Hall are not the same person
I'm reverting part of the edit made 14:16, 11 July 2012 by 63.87.61.59. That IP user seems to be a well-meaning vandal per the users' talk page, and for some reason changed Gordon Hall's name to Robert Hall, probably because Robert was an EE working on rectifiers at GE at the time, and already had a Wikipedia page that could be linked to. Gordon Hall is my uncle. I do need to dig up the patent number and cite it here. There is some language at https://sites.google.com/site/transistorhistory/Home/us-semiconductor-manufacturers/general-electric-history which mentions Gordon and the SCR development in particular, but most of that page is about Robert, which just adds to the confusion. Bill Gutzwiller's oral history at http://www.semiconductormuseum.com/Transistors/GE/OralHistories/Gutzwiller/Gutzwiller_Page6.htm describes Gordon's involvement in more detail. For now I'll cite the latter in the main article. Stevegt (talk) 15:59, 13 April 2014 (UTC)

Modes of Operation
I removed this partial sentence from the end of the Modes of Operation section, not sure what was trying to be said here: " A unijunction transistor is commonly used to trigger ". Wegsjac (talk) 15:21, 2 October 2012 (UTC)

The details about "Forward Blocking" aren't clear. It currently says "In this mode of operation, the anode is given a positive voltage while the cathode is given a negative voltage, keeping the gate at zero potential i.e. disconnected.". My question about this is - if the gate is at zero volt, then does the cathode need to be at a voltage that is below zero volt? The statement says cathode is given a 'negative' voltage. All of this is vague. KorgBoy (talk) 01:36, 16 June 2017 (UTC)

Turn-on methods section
I fixed the broken numbered list in the turn-on methods, but the following paragraph is mostly gibberish. Needs research and a rewrite. --Pstemari (talk) 09:07, 29 December 2011 (UTC)

Not a diode
An SCR is not a diode, as the erroneous definition that was added stated. They are neither functionally nor physically similar. An SCR when it is defined in terms of equivelant components is always defined as two BJT transistors. The two devices have nothing in common except that they are both multi-layer semiconductor devices. In this respect they differ in the number of layers, so that if you consider an SCR a diode, then a microprocessor is also a diode. In both cases using the device in nonstandard configurations can make them perform as a diode, but this is not typical or correct and will likely damage the SCR. AQBachler 15:25, 26 Nov 2003 (UTC)

Replace this article with a REDIRECT?
I think we should probably replace this article with a REDIRECT to the much-more-extensive article at Thyristor. How do folks feel about this?

Atlant 12:42, 25 Feb 2005 (UTC)


 * this page used to be a redirect (up until recently) to Thyristor. I think part of the difficulty was that some references define SCR and Thyristors as the same, while others don't. I'm ok with combining articles, might want to get imput from the persons who delt with this before. (see article history). Duk 16:49, 25 Feb 2005 (UTC)

I would say that the two (Thyristor and SCR) should be combined as they are two names for the same thing.Cadmium 22:38, 16 December 2005 (UTC)
 * While it is true that the terms SCR and thyristor are sometimes used synonymously, an SCR is a subset of the overall classification of thyristors. Other such types of thyristors are the GTO, MCT, the triac. It would not make sense to refer to, for example, refer to the GTO as a type of SCR. The common link for thyristors is that they are bistable devices with a pulsed gate requirement that turn on by pnpn regeneration. The SCR does not have a "controlled" turn off; the GTO does.Mak17f 23:13, 2 January 2006 (UTC)
 * Not all thyristors are SCRs - an SCR only conducts in one direction, but thyristors such as the triac will conduct in either direction. I checked with IEEE Std. 100 and they call the SCR a synonym for "reverse blocking thyristor". --Wtshymanski 18:58, 10 January 2006 (UTC)
 * Not all SCRs are made of Silicon either! The development of thyristors made from Silicon carbide has led some people to use the acronymn SCR to denote Semiconductor Controlled Rectifier. DFH 16:02, 7 May 2006 (UTC)
 * When referring to latchup in CMOS circuits, sources usually refer to parasitic thyristors, and hardly ever to parasitic SCRs. DFH 16:12, 7 May 2006 (UTC)

Anyone know what a "Jacobson circuit" is? ````Nick —Preceding unsigned comment added by 199.201.164.129 (talk) 14:10, 4 August 2008 (UTC)

A SCR is a type of thyristor, and I have seen the two terms used synonymously, I have also seen transistor used synonymously with semiconductor. A transistor is the most common type of semiconductor device, and SCR is the most common type of thyristor, but not all semiconductor devices are transistors, nor are all thyristors SCRs. —Preceding unsigned comment added by Gordongoude (talk • contribs) 04:24, 6 February 2010 (UTC)

I also think this article should be merged with the article on thyristors. The two are essentially the same thing. SCR is a term used mainly by General Electric; the rest of the world tends to use thyristor. Clampower (talk) 20:36, 19 September 2012 (UTC)

According to Bill Gutzwiller, he originally called it an SCR or simply "controlled rectifier". Thyristor was a name applied by others later, as usage spread. If there is a redirect or merge, shouldn't we keep the original name? Stevegt (talk) 18:12, 12 April 2014 (UTC)

unformated text removed from mainspace
Thyristor’s family : Power control device

Latching device

Break over voltage device.

Negative resistance device ( resistance is not follow by the ohm’s law )

FUNCTION	MAKE IT WORK	state

Power control device

Latching device

Break over voltage device.

Negative resistance device ( resistance is not follow by the ohm’s law )	-the load( light, motor, machine…) should be in series with anode –cathode(AK acts like open and closed switch) -the gate – cathode voltage (VGK ) is about 0.7v	The SCR is turn on – SCR IS FIRED. ANODE –CATHODE becomes closed switch.

SPECIFICATION :

VAK = voltage SCR when it is open = source voltage max.

IAK = current SCR when it closed ( max current)

VGK = Voltage gate – Cathode = 0.7V

VAK ( on )   = about 1v - 1.5v SCR IN DC CIRCUIT :

In Dc circuit, when Vgk = 0.7v then SCR is fired ( anode-cathode as a closed switch ) we can not turn off SCR because of the latch.However we can connect the external switch to reset SCR.

By pressing switch, the current Iak will decrease below a value called holding current Ih then SCR turn off.

Ir2 = (Vr2 – 0.7v)/ R2

SCR IN AC CIRCUIT ( LIGHT DIMMER CIRCUIT )

In AC circuit, we don’t have the latch circuit due to the change of alternating current.

By adjusting R2, we change the charging time to capacitor C, the time constant T = (R1 + R2)xC is called time delay angle or fired delay time which is the time to start firing SCR.

If R2 = max, then the time delay is longer. The light bulb became dimmest.

If R2 = min then the time delay will be shortest, the light became brightest.

EX :

R2 max = 75k then T = (15k + 75k ) x 0.47uF=42.3ms

R2 min = 25k then T = ( 15k + 25k) x 0.47uf=18.8ms

important speacification of scr ,triac
Give important speacification of scr ,triac —Preceding unsigned comment added by 117.200.192.109 (talk) 13:37, 18 June 2010 (UTC)

Article name
Why "Silicon controlled rectifier" redirects here, and not the other way around? SCR is a {Silicon {controlled {rectifier}}}: "controlled rectifier made of silicon", not a {{Silicon-controlled} {rectifier}}: "rectifier controlled by silicon". -- Mikhail Ryazanov (talk) 04:23, 21 March 2011 (UTC)

Agree - the hyphen should be dropped. Here's an ad from GE about their "revolutionary new controlled rectifier".

http://623f4c7f-a-62cb3a1a-s-sites.googlegroups.com/site/transistorhistory/Home/us-semiconductor-manufacturers/general-electric-history/GE%20Controlled%20Rectifier%201958.jpg?attachauth=ANoY7coK2Jm1dl9YptmNE_jmtzbUhEGpLQ7IUC-r2HAXprcZr-PBTSBkl450uL5xMiAfHD570vsuBWsbjVAhq42TlnyT7K2c-YOJT4C5ev4TY83jsWKii2I16qOqdK1zVCYPSgxjiUiJf2gG-AYNGte_fRJbXMEq8IkGP_5kZ8Vj3m1veGDJAA5yTV4p9GlgLxHZEgEkLHbb5e78o96wweJ2Yurhok2kM08rB7-XOOMbST7nRaZUVR0FxMR4r6etpXUDSuwq_bh2akDSdrCZh-GEWtjFVOxlQWd5NKfh2b0hIemxxx8FUEkEFtN0DwUSy4BnWMzML210D4RkOyde2nW2X-GkBNhnQg%3D%3D&attredirects=0

202.127.210.2 (talk) 08:20, 22 May 2012 (UTC)

Agree - the hyphen should be dropped. It is not a device controlled by silicon. Gc9580 (talk) 11:56, 19 April 2015 (UTC)

Does SCR stand for silicon controlled rectifier or semi-conductor rectifier?
Silicon controlled makes no sense to me as a name. The device is in fact a semi-conductor rectifier. I am familiar with the term SCR from numerous industrial projects I worked on and knew what the device did, although not my field of specialty.Phmoreno (talk) 01:50, 25 January 2012 (UTC)

It stands for Silicon Controlled Rectifier. Yes it is a semiconducter rectifier too, but so are ordinary diodes.

The "silicon controlled" part makes no sense because you're grouping the words wrong. It's not a rectifier that's "silicon controlled" but a "controlled rectifier" made of silicon, as opposed to one made of a gas-filled tube (thyratron)

It doesn't help that there's a hyphen in the Article Name that shouldn't be there. It should be removed.

The term "semiconductor-controlled rectifier" is non-standard and should be removed along with all other hyphens. — Preceding unsigned comment added by 2.123.172.140 (talk) 03:56, 14 March 2015 (UTC)

202.127.210.2 (talk) 08:13, 22 May 2012 (UTC)

"... is a four-layer solid statecurrent. "
Somebody's edit seems to have gone wrong.

Was that "current" supposed to be "device" or something else? — Preceding unsigned comment added by 173.79.157.238 (talk) 16:49, 25 July 2012 (UTC)

20 November edit
Is this edit a joke or not?! Anyone?Super48paul (talk) 10:16, 20 November 2013 (UTC)


 * Yes, but I didn't think it was funny. All edits made 2013-Nov-20 have been reverted. --DavidCary (talk) 14:35, 14 August 2014 (UTC)

Junction J1 J2 J3
This part I find confusing. Would appreciate a drawing or a better description explaining which junction is which. — Preceding unsigned comment added by 68.149.237.222 (talk) 05:25, 2 May 2018 (UTC)

India Education Program course assignment
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