Re: MOSFET GOT XTREMELY HOT




1k in series with or parallel with "-" ? and 104 makes an
"integrator"? what's the purpose? to make a pole? could you give me
more details how to get those numbers?
thanks.




On May 8, 2:50 pm, Spehro Pefhany <speffS...@xxxxxxxxxxxxxxxxxxxxxxx>
wrote:
On Thu, 8 May 2008 14:30:27 -0700 (PDT), bigca...@xxxxxxxxx wrote:

I just used the IRFP044 as picture shows but it gets extremely hot at
8A DC. It buzzed and I saw a sine wave stacked DC at Gate. Is't
caused by the linear region resistance?

got a picture from other website:

http://www.unsp.com.cn/app/pic/2006526115419.jpg

or any other reasons?

Thanks,
Powerboy

You've made a power oscillator. Reduce the gate resistor to something
like 100R. Add a 1K resistor on the inverting input. Connect 10n from
the output to inverting input.

Your MOSFET will still get extremely hot (maybe even hotter) but it
won't oscillate.

Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
sp...@xxxxxxxxxxxx Info for manufacturers:http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

.

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