基于C8051F340的开关电源模块并联供电系统设计

摘要

The system employed a C8051F340 was using as a core chip,by the sampling of output voltage and current,and the PWM control,the system achieved parallel power supply that composted of two DC/DC modules which output power is 16 W.The testing result shows that the efficiency of system power is 70.57%,the output current I1 and I2 distributed automatically accordance with 1：1and 1：2 mode respectively when the sum of I1 and I2 less than 4 A and the relative error below 2%.The system also has protect function of short circuit,and the threshold current of protection is 4.5 A.%本系统以C8051F340单片机为控制核心,通过对输出电压和电流采样计算,改变单片机PWM占空比输出,控制MOS管的通断,实现了两个额定输出功率均为16 W的8 V DC/DC模块并联供电。经测试,该供电系统供电效率为70.57%;调整负载电阻,两个模块的输出电流I1、I2之和为4 A范围内实现I1、I2按1：1和1：2模式自动分配电流,其相对误差绝对值不大于2%;具有负载短路保护功能,保护阈值电流为4.5 A。