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Is there such a thing as an insulated gate SCR or anything fitting that description?

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  • \$\begingroup\$ insulated gate for the power level of SCR became the IGBT. \$\endgroup\$ – Marla Jul 15 '16 at 1:27
  • \$\begingroup\$ Do IGBTs latch? \$\endgroup\$ – Brian Kubera Jul 15 '16 at 1:28
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    \$\begingroup\$ LOL not intentionally \$\endgroup\$ – Marla Jul 15 '16 at 1:30
  • \$\begingroup\$ sensitve gate SCR is probably the closest you'll get. or you could put a mosfet on an SCR \$\endgroup\$ – Jasen Jul 15 '16 at 1:38
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Apparently MOS-controlled thyristors were commercially available briefly, but were withdrawn due to performance issues.

enter image description here

The structure looked like this:

enter image description here

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    \$\begingroup\$ Spehro, I got very interested when this hit the news in 1983 or 1985. I had forgotten. Had such great possibilities then \$\endgroup\$ – Marla Jul 15 '16 at 1:56
  • \$\begingroup\$ @Marla I was designing in thyristors in that time period, but must have missed it. Other than the introduction of alternistors I don't think much has changed in 30+ years. \$\endgroup\$ – Spehro Pefhany Jul 15 '16 at 3:19
  • \$\begingroup\$ In the wikipedia article that you linked to there is a mention of a "MOS-gated Thyristor". I googled this term and interestingly a recent product (2014) from IXYS was ranked high in the results. \$\endgroup\$ – Brian Kubera Jul 16 '16 at 0:37
  • \$\begingroup\$ Here is the datasheet for one such device: ixapps.ixys.com/DataSheet/DS100610A(IXHX40N150V1HV).pdf \$\endgroup\$ – Brian Kubera Jul 16 '16 at 0:37
  • \$\begingroup\$ @BrianKubera nice find- and they are actually available (albeit not cheap). \$\endgroup\$ – Spehro Pefhany Jul 16 '16 at 3:10
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you can make one like this:

schematic

simulate this circuit – Schematic created using CircuitLab

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  • \$\begingroup\$ I like that Jasen. Not a single component, but seems like what the OP is wanting. +1 \$\endgroup\$ – Marla Jul 15 '16 at 1:49
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    \$\begingroup\$ I agree with Marla, however note that if you 'tease' the gate you can get a lot of power dissipation in some situations - eg. 400VDC and 100mA SCR trigger current, you could see 40W dissipation in M1 before the SCR turns on. \$\endgroup\$ – Spehro Pefhany Jul 15 '16 at 13:59
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There are several types of SCR.

Standard SCR : turns on at application of gate signal. Stays on in absence of gate signal until anode cathode current falls below threshold current level.

GTO : Gate Turn Off SCR : SCR can be commanded to turn off under certain conditions.

Insulated Gate Bipolar Transistor : IGBT : Stays on while gate signal applied.
Turns off when gate signal is removed (regardless of collector current)

Simple description of each, further search will help based upon key words. .

I don't know of any device available that fits your description

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That's it:

schematic

simulate this circuit – Schematic created using CircuitLab

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  • \$\begingroup\$ As he mentioned Insulated as Explicitly you have made this pulse transformer circuit. Its correct. But his intention is to know about as a single component rather than a circuit. \$\endgroup\$ – Photon001 Jul 15 '16 at 6:29
  • \$\begingroup\$ @Raj "insulated gate SCR or anything fitting that description", since there is no isolated gate SCR, this circuit is used to trigger SCR in many power applications, other suggested circuits (answers) based on IGBT do need separate PSU and galvanic isolation for each SCR trigger circuit. \$\endgroup\$ – Marko Buršič Jul 15 '16 at 6:40
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    \$\begingroup\$ The question asks for insulated gate SCR, which I read as "FET-like input" SCR, but this is a concept orthogonal to galvanic isolation. \$\endgroup\$ – dim Jul 15 '16 at 13:36

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