I'm trying to get a stepper motor to replicate the movement of a second hand on a clock. so i have wired up a unipolar stepper as in the two wire diagram on : http://arduino.cc/en/Reference/StepperUnipolarCircuit except without the dioide back into the com pin
I've also done a simple piece of code to get it to tick.
my problem is that the ULN2003A I'm using gets very hot quickly and then starts to fail. I'm running the stepper on the VIN power (9v from mains or battery, both tried).
is it likely to be the lack of diode causing this?