general purpose switching FET

[2000]

mosfet buz10 substitute

hello friends,

I've been using BJT for a long time, #B#C#3#3#7#, #B#C#5#4#8# 2#N#2#2#2#2# and others... but I've no experience in using FET's, could you experienced guys tell me some models that are cheap, easy to find and TO/SMD package available and multi purpose FETs?

regards,

2000

 

[meax98]

Most common are:
- BS170 small signal, 60V, 500mA
- MPF109 small signal, 20V, 100mA
- BF245 small signal, 30V, 100mA
- IRF350 power, 400V, 15A
- BUZ11 power, 50V, 30A

With this types you can substitute any FET (MOSFET).

 

[rajasekar]

Try IRFZ44. Multiple manufacturers. Its really cheap ( mass produced for UPS). Low Rdson. You can turn it on from 5V. (12V will be ideal).

Regards
Rajasekar

 

[Crisbe]

My favorite FETs with power is BUZ10 and IRF540 (nChannal-enh). Simple to use and quite fast.
For pChannal IRF9540 is a good choice (cheap).

 

[madscientist]

While we're on the subject of switching FETs, does someone have a circuit for driving a relay from an ordinary 3.3V logic level driver? How about with NPN / PNP transistors? Say I have a 5 volt or 12 volt relay that I want to drive with the 3.3V logic level driver? How would I do it with transistors or FETs?

Thanx!!!!

 

[jmk69006]

Hi,
I think you can use 2N7000 (TO-92) or 2N7002 (SOT-23),
It's rating is similar to 2N2222, detail spec. you can find from
many semiconductor manufacture.
Hope this can help.

 

[rajasekar]

If you want to use FET to drive a relay at 3.3V, use 2N2222 as first stage and use any FET.
Regards
Rajasekar