Driving a mosfet directly?

[passion1]

Thanks guys.
I am learning a lot here and I appreciate your help.
Everything is starting to make sense and my own understanding of fet's is improving rapidly!
RussMartin,George
I am using pwm and is switching using frequencies up to 20kHz.
Although it is not needed right now, I would like to accomodate higher voltages at a later stage
and for that reason I have chosen the IRFP460 which can handle up to 500V and 20A.
Right now I am trying to determine what would be the best driver (if necessary) to use with the IRFP460 specifically
because I have already tested this mosfet to work well with my application while using lower voltages,
and at higher voltages (e.g. 200V) I should never exceed 3amps current.
Thanks again for all the suggestions, it really helped a lot!

[RussMartin]

Okay, you've given us voltage and current requirement (up to 200V, up to 3A), and the maximum switching rate (20kHz).

It would still be nice to know what kind of load you are switching--

[passion1]

RussMartin

Please excuse my ignorance but I am a programmer with little electrical background until now!
I do not know what more information I can provide apart from saying that the load is a LC circuit, with only an
inductor and capacitor. The capacitor determines the current usage which is no more than 3 amps.

Correct me if I am wrong, but since I won't be needing more than 3A and taking into consideration what Paul has said earlier,
it seems that I won't be needing a driver after all?
Thanks again for your willingness to help.

[Ioannis]

Hmm, an inductor could be very dangerous to the unprotected semiconductors! Now a new part should be added: a diode, reverse biased parallel to the load (L-C). If not, the first time the MOSFET will switch off, it will probably destroyed by the EMF of the coil.

Also an approximate value of the L and C would be helpful.

Ioannis

[passion1]

Ioannis
I forgot to mention that I have included a 1N4007 diode between the drain of the mosfet and +36VDC as protection.
The inductor is 2.6mH while the capacitor is 6600 pf.

[Ioannis]

Ok. I sure would recommend a faster diode like the 1N5819, MBR360 or similar.

I think with the suggestions found in this thread you will be OK!

Ioannis

[RussMartin]

Please excuse my ignorance but I am a programmer with little electrical background until now! I do not know what more information I can provide apart from saying that the load is a LC circuit, with only an inductor and capacitor. The capacitor determines the current usage which is no more than 3 amps.

My apologies! Generically, what I and others are asking when we ask about the "load" is: "What kind of device or equipment are you turning on and off?" Is it a motor, a refrigerator, lighting equipment, or other device?

I'm sure you're not just turning an LC circuit on and off for the fun of it!