ATmega32HVB + MOSFET?

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I wonder is it possible to drive a MOSFET directly with an ATmega32HVB? Because Vcc can go to 25V.
Usually you need a higher voltage on the gate of a MOSFET to steer it fully open.

http://www.atmel.com/dyn/product...

RES

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Do you want to drive it via pwm or just on and off

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You can drive a mosfet directly with a standard AVR! Considering the datasheet specifically mentions driving p chan mosfets, one could presume it does drive mosfets.

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Is it a p-channel or n-channel. Not all mosfets can be driven by a 5 volt input but some are optimised for a Vgs of 5 volts. This is why I asked to provide a bit more info on the application

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N-channel type and driving PWM (20V amplitude), how can I drive with 5V if the MOSFET source is at 20V without any driver or driver circuit?
I was thinking about this HV AVR.(no need of extra hardware) Or is 5V more on the gate not even good enough?

RES

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Check the international rectifier site and you will find n-channel fets that will work off a 5V gate drive. I recently did a design using a standard n-channel fet driven from the micro via a MCP1416 powered from a 12 V supply and it worked very well

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I believe a 2n2222 in a "darlington fashion" would do it doesn't matter if gate is > 5v sensitive.

I drive 4 4mosfet in H(irf531) in H bridge on my atmega32, and works well on 5v, but in 12v the kickback(inductive) hits hard on my avr, so I add an optoisolator (4N25/27) and it works all fine.

I also use an optoscr(4N40) to drive a 220vDC scr in inverted-pwm mode. At 31.250 Khz works ok.

I hope it helps somebody.

I'm mexican, so I apologize for my english.