I'm controlling a 3v 3A bi-polar stepper motor with an Arduino, and found some 4-ch opto-isolated MOSFET drivers that I was able to use as H-Bridge drivers. (Drawing attached) I'm pretty sure I hooked them up correctly (the lines in red are my modifications); the led next to each MOSFET flashes in the correct sequence. However, with the stepper attached, MOSFETs #1 & #3 on both boards are getting very hot and the stepper isn't running. Any thoughts?