毕业设计-基于tl494的dc-dc开关电源设计.doc

基于TL494的DC-DC开关电源设计

摘 要

随着电子技术的高速发展,电子系统的应用领域越来越广泛,电子设备的种类也越来越多,电子设备与人们的工作、生活的关系日益密切。近年来 ,随着功率电子器件(如IGBT、MOSFET)、PWM技术及开关电源理论的发展 ,新一代的电源开始逐步取代传统的电源电路。该电路具有体积小，控制方便灵活，输出特性好、纹波小、负载调整率高等特点。 
开关电源中的功率调整管工作在开关状态，具有功耗小、效率高、稳压范围宽、温升低、体积小等突出优点，在通信设备、数控装置、仪器仪表、视频音响、家用电器等电子电路中得到广泛应用。开关电源的高频变换电路形式很多, 常用的变换电路有推挽、全桥、半桥、单端正激和单端反激等形式。本论文采用双端驱动集成电路——TL494输的PWM脉冲控制器设计小汽车中的音响供电电源，利用MOSFET管作为开关管，可以提高电源变压器的工作效率，有利于抑制脉冲干扰，同时还可以减小电源变压器的体积。

关键词：IGBT，PWM，推挽电路，半桥电路，单端正激

 
 
BASED ON THE DC-DC TL494 SWITCHING POWER SUPPLY

ABSTRACT

With the rapid development of electronic technology, electronic systems, more and more extensive applications, the types of electronic equipment, more and more electronic equipment and people work and live closer and closer. In recent years, with the power electronic devices (such as IGBT, MOSFET), PWM switching power supply technology and development of the theory, a new generation of power began to gradually replace the traditional power supply circuits. The circuit is small, flexible to control the output characteristics of a good, ripple, load adjustment rate and so on.
Switching power supply in the power adjustment control work in the off state, with low power consumption, high efficiency, wide voltage range, low temperature rise, and other outstanding advantages of small size, the communication equipment, CNC equipment, Instrumentation, video audio, home appliances so widely used in electronic circuits. High frequency converter switching power supply so many forms of commonly used with push-pull converter, full bridge, half bridge, single-ended forward and the form of single-ended flyback. In this thesis, two-side driver IC - TL494 PWM pulse output of the controller design car audio power supply in use as a switch MOSFET, can improve the efficiency of the power transformer, is conducive to impulse noise suppression, but also can reduce the size of the power transformer.

KEY WORDS:  IGBT，MOSFET，Push-pull circuit，Half bridge circuit, Single-ended forward
目　录

前　言 1
第1章 开关电源基础技术 2
1.1 开关电源概述 2
1.1.1 开关电源的工作原理 2
1.1.2 开关电源的组成 3
1.1.3 开关电源的特点 3
1.2 开关电源的分类 4
1.3 电源电路组成 4
1.4开关电源典型结构 6
1.4.1串联开关电源结构 6
1.4.2并联开关电源结构 6
1.5 电力场效应晶体管MOSFET 7
1.6 开关电源的技术指标 9
第2章 开关变换电路 12
2.1 推挽开关变换电路 12
2.1.1 推挽开关变换基本电路 12
2.1.2 自激推挽式变换器 13
2.2 半桥变换电路 16
2.3 正激变换电路 17
2.4 DC/DC升压模块设计 18
第3章 双端驱动集成电路TL494 21
3.1 TL494简介 21
3.2 TL494的工作原理 22
3.3 TL494内部电路 22
3.31 TL494管脚功能及参数 24
3.4 TL494构成的PWM控制器电路 25
第4章 TL494 在汽车音响供电电源中的应用 27
4.1 汽车音响电源简述 27
4.2 汽车音响供电电源的组成 29
4.2.1 TL494的辅助电路设计 29
4.2.2 主电路的设计 31
结 论 32
参考文献 33
致 谢 34
附 录 35
外文资料翻译 36