TB6560 3A stepper motor driver board. Features: 6N137 high-speed opto-coupler to ensure high speed without losing steps. Compatible with 42, 57, and 86 stepper motors within 3A, 2/4-phase, 4-wire, and 6-wire configurations. Automatic half decay. Excitation modes include synchronous, half step, 1/8 step, and 1/16 step. Current level is adjustable to meet your application needs. Large heat sink for good heat dissipation. Overheat and overcurrent protection circuit to ensure optimum performance. Technical data: Product type: Motor driver.