This part is a kind of semiconductor called IMT-901.

Function of this product has Microstep Constant Current Driver IC.

Manufacturers : Nanotech

Image and pinout :

Some of the text within the PDF file :

Drivers IMT-901 - Microstep Constant Current Driver “IC” The IMT 901 is a PWM chopper type sinusoidal micro step bipolar steppping motor driver. Sinusoidal micro step operation is generated by means of built-in hardware and is outputted for operation by clock signal inputting. Advantages: only one IC for power and logic (up to 2,5 A/phase) reduces considerably space, assembly time and cost of a microstep driver with a max. functions yet with a min. of ext. components. selectable from: 1/1-, 1/2-, 1/4-, 1/8-Step enables individual application-related microstep switching, smooth and constant running and reduces considerably system resonance. Current down system or current zeroing reduces or eliminates motor power losses and heating during standstill Dimensions (mm) [ ... ]

IMT-901 PDF Datasheet Download