本文设计了一种基于AT89C51单片机为核心控制器的数控直流稳压电源，该电源主要由辅助电源、显示电路、控制电路、数模转换电路、稳压电路和模数转换电路六部分组成。该系统以AT89C51单片机为控制单元，以数模转换芯片DAC0832输出参考电压，以模数转换芯片TLC1534对釆样值进行转换为数字信号。辅助电源提供各个芯片、数码管和放大器所需工作电压，显示电路用于显示电源输出电压的大小，输出电压值可通过按键对其进行步进控制（±0.1V)，并且在按键长时间按下的时候能连续增加或减小。-In this paper, the design of a based on AT89C51 microcontroller as the core controller of NC DC regulated power supply, the power supply mainly by auxiliary power supply, display circuit, control circuit, digital to analog conversion circuit, a voltage stabilizing circuit and analog digital conversion circuit of six parts composition. The system takes the AT89C51 single chip as the control unit, and the digital analog converter chip DAC0832 output reference voltage, and the sampling value is converted to digital signal by the analog digital conversion chip TLC1534. Auxiliary power supply to provide each chip, digital tube and amplifier working voltage, display circuit is used to display the size of the output voltage and the output voltage value can be through the buttons on the step control (+ 0.1V), and in the button for a long time pressed can increase or decrease.