摘要：基于单片机的数控开关电源是利用单片机实现对开关电源的输出电压设定、输出电压步进调整、输出电压和输出电流显示等数字控制。本文设计的数控开关电源由两部分组成。开关电源部分采用基于PWM控制的不对称半桥功率变换器，由模拟控制芯片KA3525产生PWM信号经驱动电路实现对功率变换电路的输出电压控制，实现电压的稳定输出。数控部分采用凌阳单片机的D/A输出对KA3525的误差比较器的参考端进行数字给定，实现对输出电压的设定、步进调整和显示等功能。文中给出了系统设计框图，对各部分电路进行了分析，并给出了必要的实验波形，经测试证实设计方法是可行的。将成熟的单片机技术与现有的开关电源技术进行简单结合实现数控，值得借鉴。 叙词：数控开关电源 不对称半桥功率变换器 凌阳单片机-KA3525 Abstract：Digital control switching power supply is the use of single chip microcomputer implementation of the switching power supply output voltage settings, adjust the output voltage step, the output voltage and output current shows such as digital control. In this paper, switching power supply design of NC is composed of two parts. Switching power supply based on the PWM control part of the asymmetrical half-bridge power converter, using KA3525 generate PWM, the use of drive circuit implementation of the power conversion circuit output control. Digital control part of the D/A using Sunplus single chip microcomputer KA3525 error output of comparator reference side of the figure given, implementation of the output voltage settings, step adjust and display functions. Mature single-chip microcomputer technology with the existing switching power supply technology for easy implementation combined with digital control. Keyword：Digital control switching power supply, Asymmetrical half