本系统基于反馈控制思想，由交直流转换电路、DC-DC变换器、步进电路模块和显示模块4个模块电路构成开关稳压电源。交直流转换电路整流部分采用全波桥式整流电路形式，DC-DC变换器以TL494有主核心设计并加上简单滤波电路及RC放电回路所构成的回路控制器。它能把脉冲宽度变化的信号转换成与脉冲宽度成正比变化的直流信号，进而实现闭环单回路控制。由单片机控制

数字定位器X9241的电阻,进而控制输出电压。显示模块由LCD1602构成。

-Based on feedback control of the system of thought, from AC-DC converter circuit, DC-DC converters, stepper circuit module and display module 4 module circuit switching power supply. AC-DC converter circuit using full-wave rectifier part of the circuit form of bridge rectifier, DC-DC converter to TL494 have the main core of the design and add a simple RC filter circuit and discharge circuit posed by the loop controller. It can change the pulse width signals into changes with the pulse width is proportional to the DC signal, and thus realize the closed-loop single-loop control. By the single-chip microcomputer to control the number of locator X9241 resistance, thereby control the output voltage. LCD1602 constituted by the display module.