The STK672-120 is a unipolar fixed-current chopper type 2-phase stepping motor driver hybrid IC. It features power MOSFETs in the output stage and a built-in phase signal distribution IC. The incorporation of a phase distribution IC allows the STK672-120 to control the speed of the motor based on the frequency of an external input clock signal. It supports two types of excitation for motor control: 2-phase excitation and 1-2 phase excitation. It also provides a function for switching the motor direction.