루프가 닫히면 스위칭 전원 공급 장치가 자동으로 펄스 폭 변조를

闭环时，开关电源将自动执行脉冲宽度调制。当系统读取键盘上的预设电压变化时，首先将比较键盘输入值和输出端子上的采样值。假设当前键盘输入值为10V，输出端的采样值为6V，其差值为4V，系统会根据此差值更新脉冲宽度以增加PWM脉冲的占空比，因此输出电压升至10V去做。同样，键盘输入值为6V，输出端子的采样值为10V，差值为-4V，系统会根据该误差值更新脉冲宽度，并减小PWM脉冲的占空比以减小输出电压。这是系统的脉冲宽度调制方法。

当环路闭合时，开关电源自动执行脉冲宽度调制。当系统读取键盘上的预设电压变化时，首先比较键盘输入值和输出端子的采样值。假设当前键盘输入值为 10V，从输出终端采样的值为 6V，差值为 4V，系统根据此差更新脉冲宽度以增加 pwm 脉冲的占空比，因此输出电压上升到 10V。同样，键盘输入值为6V，输出终端的采样值为10V，差值为-4V，系统根据此误差值更新脉冲宽度，降低PWM脉冲的占空比，使输出电压变小。这是如何调制系统的脉冲宽度。

When the loop is closed, the switching power supply will automatically change the pulse width. When the system reads the preset voltage change of the keyboard, the input value of the keyboard and the sample value of the output terminal will be compared first. Assuming that the input value of the current keyboard is 10V, the sampling value in the output terminal is 6V, and the difference is 4V, the system updates the DTY cycle of PWM pulse according to this difference, and the output voltage rises to 10V. Similarly, the input value of the keyboard is 6V, the sampling value of the output is 10V, and the difference is - 4V. The system will update the pulse width according to the error difference, in order to make the output voltage smaller and reduce the duty cycle of PWM. This is the pulse width modulation of the system.<br>