This part is a kind of semiconductor called A3967.

Function of this product has MICROSTEPPING DRIVER WITH TRANSLATOR.

Manufacturers : Allegro MicroSystems

Image and pinout :

Some of the text within the PDF file :

3967 MICROSTEPPING DRIVER WITH TRANSLATOR REF RC 2 SLEEP OUT2B LOAD SUPPLY2 GND GND SENSE2 OUT2A STEP DIR MS1 1 2 3 4 5 6 7 8 9 10 11 12 TRANSLATOR & CONTROL LOGIC VCC VBB2 VBB1 ÷8 PWM TIMER 24 PFD 23 RC 1 22 RESET 21 OUT1B LOAD 20 SUPPLY1 19 18 17 16 GND GND SENSE1 OUT1A The A3967SLB is a complete microstepping motor driver with built-in translator. It is designed to operate bipolar stepper motors in full-, half-, quarter-, and eighth-step modes, with output drive capability of 30 V and ±750 mA. The A3967SLB includes a fixed off-time current regulator that has the ability to operate in slow, fast, or mixed current-decay modes. This current-decay control scheme results in reduced audible motor noise, increased step accuracy, and reduced power dissipation. The translator is the key to [ ... ]

A3967 PDF Datasheet Download