Porter Cable 851 Driver/Drill part 698955 FET?

"BoyntonStu"

There are lots of possible replacements.

Needs to have at least a 30 volt rating and a low resistance - like 0.01 ohms.

Current rating needs to be 50 amps or more.

An " IRFZ48VPBF " is good candidate.

Unless the beastie is a logic level FET.

...... Phil

Actually, why couldn't it, and you vary the "reference voltage" to the voltage regulator to "trick" it into becoming a "current regulator?"

I can picture a circuit which could be used ...

Regards, JS

Well, basically, it could be done ... however, I "over read" this too quickly, the original poster negates some of what I advanced--only I should have read his/her words closer ... sorry.

Regards, JS

Phil or anyone,

Do you have a spare one that I can buy if I send you a SASE?

Thanks,

BoyntonStu

=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D Spend some time browsing digikey or mouser... you know you need To220 and 50A, see what they have, how much they cost etc.

Because a 7812 is still a linear regulator, and I've never seen a variable-speed drive on a cordless power tool that uses such a wasteful (in terms of energy) technique; it just wouldn't make sense to turn, e.g., half of your energy into heat when you want to drill at half speed (give or take).

one that I can buy if I send you a SASE?

Would these do?

NEW 10pcs International Rectifier N- HEXFET Power MOSFET IRFZ48V

I really do not need 5 for an old tool.

It is just an experiment.

Any gathering dust?

spare one that I can buy if I send you a SASE?

I have a pile of : IRF1010E 60V 200W 84A 330APeak 12mOhm IRF3205 55V 200W 80A 390APeak 8mOhm IRL2203N 30V 180W 82A 400APeak 7mOhm

All in TO-220 package. You are welcome to 5 of your choice. An address gets 'em thrown in an envelope. We used them in some PWM speed controls and now they are just gathering dust while waiting to be used in repairs.

Jim