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Why are FETs preffered over BJTs nowadays? Does this have to do with higher switching speed. Also, if someone says that they are preferred due to low cost, please tell the industrial rate comparison of both.

Osama Dar
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    Please back up your statements. The only thing we know here is that _you_ think that FETs are preferred over BJTs, and we don't know why you think that. It is not a general truth. – pipe Oct 06 '16 at 19:23
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    Preferred... for what? ;) – Nick Alexeev Oct 06 '16 at 19:25
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    In what context do you think "FETs preffered over BJTs nowadays"? – gbulmer Oct 06 '16 at 19:26
  • In some applications, FETs are preferred. In others, BJTs (especially for dissipation of linear power). FETs have been ousted by IGBTs (a sort of FET input, BJT output device) in many places. Do wider research! – Neil_UK Oct 06 '16 at 19:41
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    Each has advantages, BiPolar for higher V at low cost, and FET's lower RdsOn than BJT's equivalent rCE at same cost – Tony Stewart EE75 Oct 06 '16 at 20:57

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The aren't, necessarily. For some applications, BJT, IGBT, JFET, HEMT, etc. may be preferred over a MOSFET. It really depends on the application.

Now, if you're talking about why FETs are used instead of BJTs for highly integrated digital applications...it's mainly becuase CMOS is king in performance and power, and you can't do the same thing with BJTs. And companies have developed processes to make exceptionally small MOSFET transistors on chips and connect them together reliably.

alex.forencich
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