基于AVR单片机的开关电源的设计与实现_毕业设计(论文).doc

PAGE 1 毕 业 设 计 设计题目：基于AVR单片机的开关电源的设计与实现 基于AVR单片机的开关电源的设计与实现 摘 要 电源是电子设备中不可缺少的功能模块，是各种电器设备的能量的来源，其性能的优劣直接影响电子设备的技术性能与其可靠性。因此，能否设计出性能良好的电源是电子设备是否能够高效、可靠运行的一个基本保障。 本设计是以Atmega8单片机作为主要控制器，制作输出电压可以调节的开关电源。该系统不仅可以预置输出电压而且还可以调节输出电压，并具有过流保护、短路保护以及数码管显示等功能。 本论文主要讲述的是由单片机产生PWM波来控制功率管的通断。通过单片机内部集成的AD转换器检测输出电压，并和预置电压进行比较得到误差信号，调用调节函数实现稳压。单片机可以通过键盘来改变输出电压的大小，从而修改PWM波的占空比来调节输出电压的大小。开关电源的输出电压以及输出电流可以通过数码管来显示，当线路发生短路或者过载时都会通过数码管的示数显示出来。本开关电源的主要性能有稳压效果好、效率高、输出电压可调、响应速率快。 关键词：开关电源 单片机 电压可调 电压显示  The Design and Implementation of Switching Power Supply Based on MCU Abstract To electronic equipments, power is a indispensable function module. It is the energy source of all sort of electric equipment . And the performance of the power influences the technical characteristics and reliability of the electronic equipment. Therefore, it is the basic of the electronic equipments’ efficient and reliable operation that if we can design the good power or not. This design makes a power whose output voltage can be adjusted based on Atmega8 MCU as a main controller,. The system can not only preset the output voltage but also adjust the output voltage, and it has functions such as the flow protection, short circuit protection and digital pipe display. This thesis is about that PWM waves generated by MCU can control the hige power tube. It can test the output voltage through MCU integrated AD converter, and get error signals by comparison of preset voltage, and stabilize voltage by calling adjustment function. MCU can change the size of the output voltage through the keyboard modifying the PWM waves’ buty cycle. Switch power’s output voltage and output current can be show through the digital tube, and it can be show by the digital when the line short-circuited or overload happened. The switch power has a good effect to stabilize the voltage, high efficiency, and its output voltage can be adjusted, and its response speed is high. Key words: Switching power ;PW