电压可调稳压电源技术研究.doc

摘 要D/A转换芯片DAC0832及PWM控制芯片TL494组成。单片机根据输入产生8位控制信号，通过D/A转换成电压后控制TL494产生PWM 信号，驱动BOOST变换器中的MOSFET管启动，实现电压的稳定输出。TL494 自带的电压比较器接收来自输出电压的采样信号，调整PWM 的脉冲宽度，实现输出电压的稳定。同时，系统利用单片机内部A/D对输出电压进行采样，将数字信号返回到单片机，实现输出电压与输出电流的显示功能。 关键词ABSTRACT With the development of power electronics technology. Power in the various systems in the central role has become more evident. System requirements to provide long-term， stable power supply voltage. The electricity voltage instability and the traditional power output voltage difficult to achieve long-term stability of the function. Too much voltage deviations may result in permanent damage to the equipment. Switching power supply output voltage is precisely because of its long-term stability. And lightweight， highly efficient， high-reliability advantages. Gaining more widespread development and application. This paper designed to BOOST converter as the core. Supplemented by the necessary control circuit and external circuit， constitutes a switching power supply. Control module from the SCM， D / A converter chip DAC0832 and PWM control chip TL494 composition. SCM based on the input generated eight control signals. Through D / A converted into a voltage control TL494 PWM signal， driving BOOST converter MOSFET in the start， and the output voltage. TL494 built-in voltage comparator to receive the sample from the output voltage signal. PWM adjust the pulse width. Realization of stable output voltage. At the same time， the system of internal microcontroller A / D sampling the output voltage， the digital signal will return to the SCM， and the output voltage and output current display features. Key words: BOOST converters PWM control chip TL494 SCM ATmega16L 目??? 录第一章 绪论 - 1 - 1.1 开关电源的基本概念 - 1 - 1.2 开关电源的发展 - 2 - 1.3 开关电源的技术动态和要点 - 4 - 第二章 开关电源的基本分类和工作原理 - 7 - 2.1 开关电源的基本分类 - 7 - 2.2 开关电源的基本工作原理 - 11 - 第三章 BOOST变换器工作原理 - 15 - 3.1 BOOST变换器工作原理 - 15 - 3.2 BOOST变换器电路特性分析 - 16 - 第四章 电压可调开关稳压电源的设计 - 23 - 4.1性能特点及技术指标 - 23 - 4.2论文设计的方案论证 - 23 - 4.3开关电源电