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Author Topic: FET, Digital or analog? How to tell?  (Read 1753 times)
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Texas, land of the free, home of the stupid
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Jack,

Now that you have had your class in FET/MOSFET technologies,,,, Go to e-Bay and get some BSS338's, or if you have fat fingers like me, some 2N7000's,,, or you can get some 2N2222's or 2N3393's or just about any small signal NPN bipolar junction transistors to use as Gate drivers and go back to CrossRoads' post.
It ain't rocket surgery, you don't have to be exact unless you are an efficiency freek.  Have fun, tweek it until it works or smokes and then try again.

Gig 'em Aggs, or Hook 'em Horns (if you must, ugh).
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Ebay seems not to have any BSS338 . I did a search. Is that a typo?
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Good luck, Jack

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jack,
STP40NF10L
digikey.com
10 of them for about $20
reasonable
they're very low "on-state" ohms

BTW - It's not "logic" vs "analog", it's "logic level" vs everything else.
"Logic level" means they get turned on right with a logic level ("5V") voltage (the others require more, much more.)
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Thanks, Runaway, I am slowly catching on with all the help given on the forum. I tried again to order some FETS for general use, and just oredered these http://www.ebay.com/itm/250795972359?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649. $0.92 each in lots of 10.
Any suggestions as to whether they will be of general use or not?
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Good luck, Jack

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Why such an expensive part?
http://www.digikey.com/product-detail/en/NTD5867NL-1G/NTD5867NL-1GOS-ND/2401422
I think this would do the job too, just 52 cents each vs over $2 each.
And they have lower input capacitance so they'll switch faster.
http://www.digikey.com/product-search/en?vendor=0&keywords=STP40NF10L
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Designing & building electrical circuits for over 25 years. Check out the ATMega1284P based Bobuino and other '328P & '1284P creations & offerings at  www.crossroadsfencing.com/BobuinoRev17.
Arduino for Teens available at Amazon.com.

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And it doesn't have 3 week shipping from China.
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Designing & building electrical circuits for over 25 years. Check out the ATMega1284P based Bobuino and other '328P & '1284P creations & offerings at  www.crossroadsfencing.com/BobuinoRev17.
Arduino for Teens available at Amazon.com.

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jack,
Those would be OK, for your "2A" purpose.  5V for those guys is like a minimum "on" voltage.
My suggestion leaves room (current-wise) to grow into.
I used the STP... in my "e-chopper".
CrossRoads's suggestion is a good deal, too; less dough, buy more stuff, win-win.

And, in case you didn't know, DigiKey is a primo source (supplier).

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Yes, you'd be surprised how often e-bay is not the deal you'd think it would be.
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Designing & building electrical circuits for over 25 years. Check out the ATMega1284P based Bobuino and other '328P & '1284P creations & offerings at  www.crossroadsfencing.com/BobuinoRev17.
Arduino for Teens available at Amazon.com.

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