Electrical Engineering - Driving large power MOSFETs ?

Author

Driving large power MOSFETs ?

2007-05-09, 5:25 pm

I need to drive a power MOSFET with an op amp.

What do I need between the op amp and the MOSFET ?

Thanks.

Palindrome

2007-05-09, 5:25 pm

me wrote:
> I need to drive a power MOSFET with an op amp.
>
> What do I need between the op amp and the MOSFET ?
>
http://www.headwize.com/projects/opamp_prj.htm

For more, you need to specify which op amp, which MOSFET and what
application...

--
Sue

2007-05-09, 8:25 pm

On Wed, 09 May 2007 22:07:28 +0000, Palindrome wrote:

> me wrote:
> http://www.headwize.com/projects/opamp_prj.htm
>
> For more, you need to specify which op amp, which MOSFET and what
> application...
>

I've got the transfer function and all that figured out. No problem there.

I'm using an LM324 to drive a IFXH20N60. (20A, 600V with built in diode...)

Someone once told me about putting a cap in the gate circuit to enhance
the life of the MOSFET. But I don't remember why.

The gate looks like a small capacitor, right ? If so, do I need a
resistor to ground to drain the cap when the op amp output goes to 0 volts
? Or will the output of the opamp sink current from the gate ?

Thanks

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