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Old 20th January 2013, 09:44 PM   #1
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Default IRFP240 source?

Are the IRFP240s becoming scarce now? I couldn't find them on mouser or anywhere else "reputable." Any suggestions for where to get these? Maybe my mouser search was bad? Or maybe someone has had good luck with a particular ebay seller? I'm looking to get quite a few so I can match them myself.
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Old 20th January 2013, 09:55 PM   #2
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enter IRFP240pbf in the search engine
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Old 20th January 2013, 10:00 PM   #3
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Farnell still has 2439 of them in stock.
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Old 20th January 2013, 10:01 PM   #4
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Quote:
Originally Posted by jackinnj View Post
enter IRFP240pbf in the search engine
Ah, ok. Not a great search engine, is it?! Thanks!
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Old 20th January 2013, 10:03 PM   #5
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While I'm on the topic... Any guidance on what number you need to purchase to get good matches? Let's say you need to match 4 closely. You need to buy... 20?

Similar question on the IRF9610s although I would guess the answer would be about the same.
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Old 20th January 2013, 10:19 PM   #6
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Depends upon how closely you want them to match -- if you purchase a tube you should get enough devices for 2x 4 sets +/- 0.02V.

I found that within a tube, when you match for Vgs the transconductances generally line up pretty well.
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Old 20th January 2013, 10:22 PM   #7
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Sorry for the newb question, but how many in a tube?
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Old 20th January 2013, 11:29 PM   #8
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Quote:
Originally Posted by oneplustwo View Post
how many in a tube?
25 pieces
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Old 21st January 2013, 01:06 AM   #9
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I've used these as an alternative to the irfp240, they work pretty well. You should have no problem matching 4pcs within a tube, I'd be skeptical purchasing semis from ebay; matched or otherwise.

FQH44N10_F133 Fairchild Semiconductor | Mouser

Last edited by MEGA_amp; 21st January 2013 at 01:09 AM.
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Old 21st January 2013, 01:41 AM   #10
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You need matches only for the ones in parallel. Most of the time 0.1V
at the operating point is good enough, and you can probably get 5 groups of
4 out of a tube.

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