SMAKN TB6600 Upgraded Version 32 Segments 4A 40V 57/86 Stepper Motor Driver 9V-40V DC power supply.Use the new upgrade the chip version5 year warranty H-bridge bipolar constant phase flow driver. The maximum output current is 4.0A (eight optional). Up to 32 segments of six kinds of sub-modes available. The input signal high-speed photoelectric isolatio .