Hey guys, I ve seen so many examples of these driver boards to power a 5v stepper motor using an external 5vpower source... but what if i do not have a power supply..I have a 9 v battery to connect to the ULN2003A driver board but wouldnt that be 4v too much, is that a problem.
2donboi2:
Hey guys, I ve seen so many examples of these driver boards to power a 5v stepper motor using an external 5vpower source... but what if i do not have a power supply..I have a 9 v battery to connect to the ULN2003A driver board but wouldnt that be 4v too much, is that a problem.
Depends.
The ULN2003 chip itself can handle up to 50volt.
The ULN2003 can only drive small high-impedance motors.
A higher voltage means more motor current, which could be a problem for the ULN2003.
Most 9volt batteries can't provide the current for a motor anyway.
Maybe better to leave that 9volt battery in the smoke alarm.
Leo..
Small 9V batteries are good for low current loads only. The NiMH rechargable ones (typically 8.4V) are
better and can handle small motors, but the higher voltage here means the stepper may overheat. I presume
this is a 28BYG-48 unipolar stepper?
Hi,
What is your stepper?
Thanks.. Tom.. 
TomGeorge:
Hi,
What is your stepper?Thanks.. Tom..
The step motor i am using is the 28BYJ-48
Hi,
Try 4 x AA batteries in series, that will give you 6V, the stepper and module will tolerate that voltage and it will have the capacity to give you some reliable stepper response.
Tom...