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Topic: FET, Digital or analog? How to tell? (Read 2196 times) previous topic - next topic

123Splat

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).

jack wp

Ebay seems not to have any BSS338 . I did a search. Is that a typo?
Good luck, Jack

Runaway Pancake

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.)
"Hello, I must be going..."
"You gotta fight -- for your right -- to party!"
Don't react - Read.
"Who is like unto the beast? who is able to make war with him?"

jack wp

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?
Good luck, Jack

CrossRoads

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
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

CrossRoads

And it doesn't have 3 week shipping from China.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

Runaway Pancake

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).

"Hello, I must be going..."
"You gotta fight -- for your right -- to party!"
Don't react - Read.
"Who is like unto the beast? who is able to make war with him?"

CrossRoads

Yes, you'd be surprised how often e-bay is not the deal you'd think it would be.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

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