thanks for your help and advice, but still I don't get it!
how can the motor turn when it draws more current than 40mA???
The printer can't operate from the arduino output pin.
The current it requires is supplied by the external power supply , which is switched by the mosfet
in link I supplied:
This
link(Disregard the +12V motor voltage, and substitute your 9.5V motor voltage.)
As you can see, the motor is NOT powered by the arduino output pin.
Is powered by the 9.5V supplied by the dc to dc buck converter which is powered by the 12V power supply.
(reread my last post)
The arduino ouput pin drives the mosfet.
The code does not change. The same output pin that you previously had the printer connected to is
now connected to the mosfet gate.
The printer motor that was connected to the arduino output pin is now connected directly to 9.5V
on one end and the mosfet drain on the other.
If you only have access to one side of the motor and are not able to rewire it the way it is shown, then
you can use a P-channel mosfet as a
high side switchHere is a logic level
P-Channel Mosfet that can switch the 9.5V when placed between the 9.5V supply
and the motor .
The arduino output goes to the mosfet gate pin.
FQP27P06 datasheet