This part is a kind of semiconductor called PMM8713PT.

Function of this product has Universal Controller IC for the 2-Phase Stepping Motor Drive.

Manufacturers : ETC

Image and pinout :

Some of the text within the PDF file :

HIC (AC power input) Universal Controller IC for the 2-Phase Stepping Motor Drive PMM8713PT Outline The universal controller “PMM8713PT” is the gate array IC (HIC) to control the 2-phase stepping motor drive. This product has been developed for the purpose to further simplify 2-phase stepping motor use, as combined only with switching elements or power hybrid ICs to configure a 2-phase stepping motor driver. Characteristics • Universal controller • • • • Source voltage High output current High noise margin 2 types of pulse input : The following 3 types of energization mode can be selected by switching at the energization mode switching terminal 1EX / 1-2EX / 2EX : Vcc=4.5~5.5V : 24mA min (sink, source) : Schmitt trigger circuit is incorporated for the all input terminals. [ ... ]

PMM8713PT PDF Datasheet Download