parallel port stepper driver (UIM24004) Miniature Size 42.3mm*42.3mm*13.5mm, NEMA size 17 Integrally designed to fit onto stepper motors seamlessly, as well as work standalone. Wide range power supply 10-40VDC, Max 4A per Phase settable output current, full, half, quarter and 16th Microstepping Dual H-bridge with PWM constant current control Enable/shutdown controllable Opto-isolated inputs with common anode Die-cast aluminium heat-sink enclosure DIR, SPD, CUR, STP, Microsteppers Idle Current Reduction Further more stepper controller with rs232 and CANbus stepper controller and smart self-pulsing stepper controller are available.