为了提高小内阻步进电机驱动系统中功率MOSFET的开关速度,采用ICL7667作为功率MOSFET的驱动器来实现步进电机的高频斩波控制。对驱动电路采用的功率MOSFET的栅极电容特性、开关时间等进行了研究,发现栅极电容的充放电过程影响了功率MOSFET的开关速度,提出了提高功率MOSFET开关速度的方法。最后,采用ICL7667作为功率MOSFET的驱动器实现了步进电机的高频斩波控制。仿真和试验结果表明:采用ICL7667的驱动电路,可以保证斩波频率为200 kHz时,功率MOSFET的漏极输出仍处于截止和深度饱和的状态,这比采用电阻分压式驱动电路其斩波频率最大为20 kHz提高了10倍,可保证小内阻步进电机在高速斩波信号的控制下正确运行。

ICL7667 was used as a power MOSFET driver in stepper motor drive system in order to increase switching speed of the power MOSFET and to realize high-frequency chopping control for stepper motor.The gate capacitance and switching time of the power MOSFET were studied.The results show that the charge and discharge processes of gate capacitance affecte the switching speed of power MOSFET.So a method increasing the switching speed of the power MOSFET was introduced.Finally,ICL7667 was used as a power MOSFET driver to achieve a high-frequency chopping control for stepper motor.Simulation and test results indicate that the chopping frequency by using ICL7667 can reach up to 200 kHz when the power MOSFET is still in cut-off or deep saturation,which has increased by 10 times as compared with 20 kHz by using voltage division with resistor.In proposed system,stepper motor can run correctly under control of high-speed chopping signal.