毕业设计_车载章功率放大器设计.doc

河南理工大学万方科技学院本科毕业论文 PAGE PAGE I毕业设计_车载章频功率放大器设计摘?? 要 电子信息技术几乎主宰了整个电器行业的发展，随着电子技术的进步发展在功率放大器的设计上功能也不断更新。功率放大器在家电、数码产品中的应用也越来越广泛，与我们日常生活有着密切关系。随着生活水平的提高，人们越来越注重视觉，音质的享受。在大多数情况下，增强系统性能，如更好的声音效果,是促使消费者购买产品的一个重要因素。音频功率放大器作为音响等电子设备的后级放大电路，它的主要作用是将前级的音频信号进行功率放大以推动负载工作，获得良好的声音效果。同时音频功率放大器又是音响等电声设备消耗电源能量的主要部分。 目前，音频功率放大器仍以模拟功放为主流产品，模拟功放经历了数十年的不断改进和完善，其技术已发展到了顶峰。模拟类功放是以线性放大为基础，功率放大器件有电子管和晶体管两类。按功放静态工作点的设置可分为Ａ类放大，Ａ/Ｂ类放大和C类放大三种。晶体管功放的最大优点是电源转换效率高（C类功放最大可达55%）、体积小、重量轻、发热量不大、生产成本低。缺点是转换速率低、偶次谐波失真较大。音质和可靠性指标都略逊于电子管功放。随着晶体管制造技术的不断提高和新技术的应用，各项实用性指标和可靠性指标都有很大改善，并不断在向更大的输出功率、更小的体积、更轻的重量、更多的功能和智能化方向发展。本文介绍了音频功率放大器构成、功能、及工作原理等。音频功率放大器从电路从结构上来分有，OTL，OCL，BTL。采用LM1875和TDA1521放大是构成本产品主要部件，接下来将设计方案原理制成PCB板，通过原理图及所要元件焊接电路板，在对电路板进行测试最终完成设计任务。关键词：LM1875功率芯片 音频功率放大器 PCB 车载AbstractElectronic information technology has dominated the appliance industry is almost the development of electronic technology, with the development of the design in power amplifier functions are constantly updated. Power amplifier, digital products in home appliance and more extensive application, and our daily life is closely. As standard of living rise, people pay more and more attention to visual and audio enjoyment. In most cases, enhance the system performance, such as sound effect, it is better to consumers to buy the product is one of important factors. Audio power amplifier as acoustics electronic equipment level amplifier circuit after, its main function is to the audio signal before class to promote the work load power amplifier, obtain good effect. While audio amplifier is acoustics acoustic equipment, the main part of the power consumption.At present, audio amplifier with analog amplifier is still the mainstream products, experienced decades of amplifier improvement continuously, the technology has already developed into peak. Such amplifier is simulated based on linear amplification, power amplifier device has tubes and two classes. Transistor Ac