单片机控制下可变输出电压的电源设计  

Design of variable output voltage power supply controlled by MCU

作　　者：陈菁[1] 张万 

机构地区：[1]北京林业大学理学院,北京100083

出　　处：《现代电子技术》2018年第2期91-94,共4页Modern Electronics Technique

基　　金：北京林业大学2016年度教学改革研究项目(BJFU2016JG044)~~

摘　　要：针对目前使用的开关电源几乎都采用旋钮开关调节电压,调节精度不高,而且经常跳变,使用麻烦的缺点,设计一种基于STC12C5A60S2单片机的可变输出电压的电源,使其功能更加完善并提高智能化程度。它产生两路47 k Hz的PWM脉冲信号,分别经过MOS驱动IC IR2104控制两个BUCK电路。单片机内部自带的10位ADC能通过电压电流检测电流实时反馈两路的电流和电压数值,并由此调整输出的PWM的占空比,形成电压闭环控制系统。设计按键能设置输出电压的大小、液晶屏显示实时输出电压与电流。测定显示在额定电流1 A输出的情况下,满载的供电效率为82%,输出电压误差小于0.15 V。As the rotary switch is mostly used in the current switching power supply to regulate the voltage,which has low regulation precision, frequency hops and troublesome operation, a variable output voltage power supply based on the STC12 C5 A60 S2 microcontroller was designed to further enhance its function and improve its intelligence level. The power supply produces two 47 KHz PWM pulse signals which control two BUCK circuits respectively by making MOS drive IC IR2104. The MCU with built-in 10-bit ADC can feed back the current and voltage values of the two signals in real time by voltage and current detection,and regulate the output duty cycle of PWM to form a voltage closed-loop control system. The button can be designed to set the output voltage value,and the LCD screen can display the real-time output voltage and current values. The test shows that the full-loaded power efficiency is 82% and the error of output voltage is less than 0.15 V under the condition of 1 A output rated power.

关 键 词：开关电源 BUCK STC单片机 IR2104 可调输出 精确控制 

分 类 号：TN911-34[电子电信—通信与信息系统] TN958[电子电信—信息与通信工程]