1. This paper presents a method of stepping motor microstep driving based on the analyses of current waveform.

2. It seems that the microstep driving technique is one effective measures to improve controlling precision of the step motor.

3. Adopting the new microstep to subdivide algorithms makes cutting high quality while cutting at a high speed, the curve is smooth and more evasive.

4. One is the first introduction of PLD device and ISP technology to the design of phase sequencer, the other is the new measure and amend method of microstep.

5. In this paper, a new idea about the analysis method of torque vector is introduced. Based on the analysis method, the step motor as an example is analysed for microstep driving technique.

6. It is presented in the paper that SIN subdivide microstep driving system with microprocessor controlled for three phase hybrid stepping motor synthesises both software and hardware.