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Author Topic: motor with own power throw transistor  (Read 616 times)
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Hello
i want to connect battery with 12V,10A to motor and then control it throw PWM
there is  scheme

i use IRF1018E
Problem:current of motor 3-4A,but it have to be 10A
sorry for my english
and there is some noise which going from motor,why it happens?
« Last Edit: March 06, 2012, 03:20:06 pm by boyma » Logged

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Problem is most likely that the MOSFET is not a LOGIC LEVEL MOSFET and the arduino output pin cannot fully turn on the device. While turned on, take a voltage reading between the drain terminal and ground. If it's not zero or just a few millivolts then the device is not turned on fully.


Lefty

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Always ensure you get a MOSFET that is described as "logic level" in its datasheet - only these can be controlled directly from 5V.

The vast majority of TO220 packaged MOSFETs are NOT logic level...
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thanks for your answers
can i use FQP30N06L? here he's datasheet http://lib.chipdip.ru/226/DOC000226423.pdf
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thanks for your answers
can i use FQP30N06L? here he's datasheet http://lib.chipdip.ru/226/DOC000226423.pdf

Yes, that is a logic level power mosfet.

Lefty
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strange but with this transistor similar problem+he strongly heats
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strange but with this transistor similar problem+he strongly heats


Measure the drain voltage to ground while under load and state the value you find. Also measure the current flow to the motor and state it's value. Do these measurements while just wiring +5vdc to the gate, not using the pwm signal from the output pin.

Lefty
« Last Edit: March 07, 2012, 03:38:32 pm by retrolefty » Logged

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if i disconnect 3V ,then I=5A
smth strange
« Last Edit: March 07, 2012, 05:20:57 pm by boyma » Logged

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if i disconnect 3V ,then I=5A
smth strange

Ok, you've got it wired wrong. You should wire an N channel mosfet as a 'low side' switch, not a high side as you have. Wire +6 to motor, wire other motor lead to drain, wire 6v negative to source terminal and to negative of 3v supply. Also you should wire a 10k resistor from gate to source terminal to drain off gate capacitance when gate voltage is removed.

Lefty
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