L297 chip generates pulse phase sequence signals of which the pulse width is adjustable. The signals are the input ones of dual bridge driving circuit and drive the stepper motor after amplification.
L 297芯片产生脉宽可调的脉冲相序信号，该信号作为双极性桥式功率驱动电路的输入信号，放大后驱动步进电机。