I have a small motor, very small. I can recall running it by directly attaching 2 AA batts to it (in series - so 3v). I recently hooked it up to a hbridge with a 6v power supply (motor power), and as soon as I turn it on, the motor revs up, stays at what seems to be max RPM for about a sec, then goes down to no movement, only emitting a squealing noise of some sort. the motor doesn't get hot, atleast, not for the 10 seconds or so that I left it on once it revs down and stops. Since the hbridge i'm using has a max output of 1A, could the behavior of the motor be explained by lack of ample current?
*if it helps, I tested further with the same setup but with a 9v instead of 6v, and achieved similar results, although the motor seemed to rev even higher at max RPM, and lasted slightly longer as well.
It would be best if you could measure the current being drawn by the motor during your testing to see what is what. Could be your motor driver H bridge is going into an over current shutdown mode or something.
Yes, so it seems I was right about the lack of current. Although I wasn't able to figure out exactly how much my little motor pulls at 6v, I am sure its about 2 or perhaps 3A, if not more. anyway, since the hbridge I have atm only supplies up to 1A, I was forced to look for a higher current motor driver, and found this:
Drives two motors and 6v, so it is basically exactly what I need. Hope this helps.