Motor + arduino power source?

I am adding a 12v DC motor into an arduino circuit. The motor will be switched on and off controlled by a transistor controlled by arduino. Should the arduino be powered by the same ~10v power source, or should the motor power source and arduino power source be separate (but have a common ground). (The reason I am using ~10v is because I have 8 NiMH AA batteries as my power source for the motor and it runs just fine at that voltage.)

iceng6 years ago
It can be, if you put a big capacitor 1000 uF 25 VDC next to the motor.
Run a 1N4001 diode to a 100 uF 15 VDC to the regulator for your uP.
A common ground is necessary unless you use an optical isolator to
control the motor power transistor.