muki55

Try this simpliest PWM

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	pwm1.JPG (62.6 KB, 222 views)
	pwm2.JPG (53.2 KB, 200 views)

svdv

Hello the circuits seems good to for study. I would like to know the specifications of Q2, the power MOS and the diode to be place across the load.

Thanks in advance.

audioguru

The spec's must match your load's requirements and the switching frequency.
You can lookup the spec's in Google or at www.datasheetarchive.com like everyone else does.

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Uncle $crooge

audioguru

Won't your beer can freeze to your mouth?

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Uncle $crooge

AirWalker83

hi, everybody........
i need some help here.......
i am using power window motor for my project.....
Now i am searching a suitable motor driver in IC package for the power window motor.....
As i know, the L293B is not suitable because it only support up to 1A per channel.......
So, do u all have any suggestion of the motor driver for the power window motor???

chiba

Your choice is simple: drive a mosfet and live in peace, or pursue your present course and your ic's face obliteration. We shall be waiting for your answer. The decision rests with you.

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2.4Gigglehurtz

AirWalker83

Mosfet need to build the circuit?
Cause i still a beginner, not quite understand the MOSFET.
Beside MOSFET, got any other motor driver IC that can replace L293D?

chiba

Do you like Salsa? because trying to drive a Window winder that could draw anywhere from 5-30A is going to bake all your chips. However, using a simple low cost ic to drive one of them awfull mosfet thingys will work out cheaper and easier. I'm sure PWM ic's that can handle 30A are available in the future but first we have to get that time line thing sorted.

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2.4Gigglehurtz

Hero999

No, not that I know of anyway. I recommend that you should do some Googling and research about MOSFETs, they're not that complex, they're basically electronic switchs.

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Get Opera it's simply a superb browser.

tankist80

all, thanks for the info. lurked for month's now and learned a lot of things.
i plan to build H bridge for wheelchair motor and IRF3205 looks very suitable. at least on paper looks like significant improvement over ifrz44n (and not much more expensive) i thought using first.

any recomendations for a VERY good one ? HIP4081??

AirWalker83

hi everybody.......
I had saw the datasheet of L298N which the current limit can be raised up by parellel the 2 H-Bridge in the IC. Actually it raised up to how many ampere?
i hear that u all sugest to use power MOSFET, but i actually still dun understand how it can become motor driver???can somebody help?
Or is ther any motor in the market have the same torque as power window motor but will draw less current?
thanks...........

audioguru

A Mosfet can switch many amps of current without much waste (heating).
The IRF3205 mentioned can conduct 30A and heat only 7.2W.

If you reduce the current for a motor then its torque becomes less.
A gearbox allows a low-current motor to have more torque but its action is slower.

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Uncle $crooge

AirWalker83

thanks for your explaination. Then u have any circuit uisng IRF3205 to build dc motor driver???

Sceadwian

Take any of the thousands of readily available mosfet motor driver circuits and just replace the FET used with an IRF3205 (makeing sure the drive voltages are still acceptable)

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AirWalker83

hi, i just buy a motor driver kit for my power window motor.
It can suipport up to 10A. I think it got 2 relays in the circuit.
i had sucessfull testing for the motor to run.
But for the PWM speed control, i didn't manage to do it.
At the spec, it say it can be used for speed control.
is it that is different way for PWM control using relay?
So, did anyboy have any idea regarding this problem?
Thanks