脉冲宽度调制（PWM）是英文“Pulse Width Modulation”的缩写，简称脉宽调制。它是利用微处理器的数字输出来对模拟电路进行控制的一种非常有效的技术，广泛应用于测量，通信，功率控制与变换等许多领域。一种模拟控制方式，根据相应载荷的变化来调制晶体管栅极或基极的偏置，来实现开关稳压电源输出晶 体管或晶体管导通时间的改变，这种方式能使电源的输出电压在工作条件变化时保持恒定。　　脉冲宽

-Pulse width modulation (PWM) is the English " Pulse Width Modulation"　acronym, or pulse width modulation. It is the use of the microprocessor to the digital output of analog circuits for the control of a very effective technology, widely used in measurement, communications, power control and many other fields with the transformation. An analog control means, in accordance with the corresponding changes in load modulation transistor gate or base bias, switching power supply to achieve the output transistors or transistor on-time changes in power in this way can the output voltage in the workplace conditions of constant change. Pulse width