The function of phase memory in stepper motor driver

When the stepper motor driver is powered off in a certain phase, if it is different from this phase in the next power on, the stepper motor will appear "jitter". In order to eliminate this jitter phenomenon, the phase of power off must be memorized.

The running time sequence of the stepping motor is 8. Suppose that the motor stops at step 4 and cuts off the power. After the motor is powered on again, if the motor starts to drive directly at position 4, a skip step will appear at step 1. If the system can still remember that it is still in step 4, then it can correctly issue the command to go to step 5 or step 3.

At present, most stepper motor drivers have no power-off phase memory function, especially the stepper driver with common special IC. After the special IC is powered on, the reset signal of the reset pin will reset the motor phase to the initial value, and the power on jitter should be unavoidable. Even if the absolute value of the servo motor is used, it has to be judged and corrected, which can also be regarded as jitter. Or strictly speaking, there is no motor that does not vibrate when powered on. The key is how much impact this jitter has on your application. It is better to record the absolute stop coordinate, reset the system after power on, check the origin, and then run to the absolute coordinate before power off to resume operation.