Concerning the mc3749 chip, I use 4 2n3055,s to the steppers. The board is on 8 volts regulated with a 7808 and the steppers operating on 24 volts 5 amps. I think you could boost it to what you want as long as the power transistor's can handle it. My stepper is also from a printer and I am going to use more for a foam cutter/gantry style combination. This will be cnc.
John |