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Old March 2nd 09, 03:16 AM posted to rec.radio.amateur.homebrew
Leland C. Scott Leland C. Scott is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 44
Default If a mosfet works fine than why not use a thyristor ?


"D. v. Bilt" wrote in message
...


It just crossed my mind. If a mosfet used in switch mode should or
could a thyristor also work.


Yes they would however the circuit complexity is higher. Other than the
frequency issue the problem is turning off the SCR. This requires some
careful design techniques to commutate the SCR off once it is turned on.
That's where the complexity comes in to play. Various methods are used to
accomplish this. Also SCR's have other problems too such as turn-on di/dt
limits, dv/dt limits at turn off (which can cause retriggering), recovery
time requirements, high recovered charge etc making snubber circuit design a
challenge.

http://nptel.iitm.ac.in/courses/Webc...)NPTEL)%20.pdf

http://forum.vtu.ac.in/~edusat/Prog6...niques.ppt#113

--
Regards,
Leland C. Scott
KC8LDO


Do manufacturers make them already
for high frequencies ?
Because a power mosfet is far too expensive to hobby around with.