The constant current driver is a constant current chopper power amplifier. When the output current determined, the driver can obtain different output power by adjusting the driving voltage, then the driving conditions could have different driving voltages. The output torque of the motor decreases as the speed increases, mainly reason is the stator winding inductance. As while as the input voltage goes larger, the average current of the motor at high speed is larger and the performance at high speed is better.

The input voltage of the drive is higher than the voltage across the motor. The difference is determined by the drive circuit of the driver: whether the driver adopts a full-bridge or a half-bridge mode, there will be a voltage drop loss caused by the switch tube, which is generally around 0~0.6V. In addition, in the design of the drive circuit, other devices voltage drop may loss.

The drive parameters of Stepper Motor Search Tool based on the conventional drive settings. Different drive configuration method has a great impact on the output torque. For example, the smoothness of the whole step is not as good as the subdivision method, but the maximum torque performance will be better than the subdivision method; if the motor is equipped with a position sensor, the phase angle between the current and the magnetic flux can be accurately controlled, then the relative position open-loop drive mode is easier to achieve the maximum torque.

Generally, the input condition setting of the drive will directly affect the output of the motor. When the driving conditions of the motor are determined, the efficiency difference, nonlinear distortion rate, heat dissipation performance, and parameter selection between different drivers will also affect the output of the driver.

The temperature rise and speed curve is obtained by calculating the temperature rise data of the motor at different speeds. The temperature rise calculation is to multiply the loss of the motor by the thermal resistance. The loss is divided into copper loss and iron loss. The thermal resistance is the motor plus the specified Thermal resistance after mounting the board; stepper motor has low efficiency, large current, and high harmonic components. The driving voltage will affect the current during the motor operation and the hysteresis eddy current effect of the iron core, affect the loss of the motor, and then affect the temperature rise .