[ Abstract ] This paper discusses stepper motor microstepping technology based on the principle of constant amplitude uniform rotation of current vector. A microstepping drive mode based on SPWM control using a microcontroller is designed, and various microstepping levels can be achieved through software data settings. Furthermore, a current feedback loop is introduced to correct errors, realizing precise operation control of a hybrid stepper motor. [ Keywords ] Stepper motor; Microstepping drive; SPWM; Closed-loop control A stepper motor is a digitally controlled motor that converts electrical pulse signals into corresponding angular displacements, possessing the ability to start and stop quickly. When the load does not exceed the dynamic torque value provided by the stepper motor, it can start and stop instantaneously. Its step angle and speed are unaffected by voltage fluctuations and load changes, as well as environmental conditions such as temperature, air pressure, shock, and vibration; they are only related to the pulse frequency. It has a fixed number of steps per revolution, and without missing steps, its step error will not accumulate over time. In systems with low precision requirements, open-loop control of stepper motors is entirely feasible, and therefore, they have been widely used as actuators in automatic control systems. Stepper motors emerged in the last century. Besides changes in manufacturing processes and precision, the main development of stepper motors has focused on the control and drive of the motors. Performance optimization for stepper motors primarily focuses on two directions: first, ensuring a smooth acceleration and deceleration process to prevent step loss or overshoot during high-frequency acceleration and deceleration; second, utilizing stepper motor microstepping technology to guarantee good precision and smooth operation. With the development of microprocessor technology, research and applications in these two areas are becoming increasingly widespread. The following section focuses on research into microstepping. [b][align=center]For more details, please click: Research on Microstepping Drive Technology for Stepper Motors[/align][/b]