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how to drive the MOSFET

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javed

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how to drive a mosfet

Dear All

I construct a UPS. I use the Power MOSFET with replacement of Transistor. When UPS in UPS Mode, the UPS works OK. But when UPS in charging Mode the MOSFET are getting very hot. Why???? Can anyone help me in this problem.

Thanks in advance.


Javed
 

quinn

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how to drive mosfet

Hi
What are you driving the gate of the mosfet with?

is the mosfet high side or low?

Without seeing the charging circuit etc its difficult to tell but id guess the current draw during charging is greater than when in UPS mode? (particularly if the battery is low)

You have to be carefull with the ON resistance and also the intrinsic diodes on some mosfets.

If you provide more info im sure someone can help. Even a rough sketch or block diagram.

Chris
 

TekUT

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how to drive a mosfets

@javed

Could you plz post the circuit schematic, we can take a look on it and help you.

Bye
Powermos
 

osmanpasali

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block diagram ups

there are special ic's for driving mosfets....
 

randell_xtian

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you can drive the MOSFET by giving it an oscillation/trigger by turn-on/turn-off at a certain pulse(time) or frequency at the GATE terminal. hmmm, what is the Id current actual measured? the rated Vds? and the measured Vds?

you can used the BJT as a trigger mechanism for the MOSFET.

best regards,
randell_xtian :D:D:D
 

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