Talk:Silicon controlled rectifier

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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)[reply]

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)[reply]

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)[reply]

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)[reply]

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)[reply]

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

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)[reply]

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)[reply]

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)[reply]