模拟电子技术课程设计--扩音机.docVIP

模拟电子技术课程设计说明书 扩音机 院 系： 电气与信息工程学院 学生姓名： 指导教师： 职称 专 业： 电气工程及其自动化 班 级： 完成时间： 2012年6月2日 摘 要 扩音机是生活中很常见的一类电子产品，使用非常广泛。扩音机电路是把微弱的声音信号放大成能推动扬声器的大功率信号，电路结构分为前置放大，音调控制部分。 前置放大主要完成小信号的放大，一般要求输入阻抗高，输出阻抗低，频带宽，噪声要小音调控制主要是实现对输入信号高、低音的提升和衰减；由于集成运算放大器具有电压增益高、输入阻抗高等优点，用它制作的音调控制电路具有电路结构简单、工作稳定等优点扩音机前置放大音调控制 ABSTRACT Megaphone is very common life of a class of electronic products, the use of it is very extensive. Amplifier circuit is put the faint sound amplification can push into the high-powered signal, circuit structure is mainly divided into the preamplifier, tone control two parts. Preamplifier main perform small signal amplifier, general requirement high input impedance, output impedance low, wide frequency band, the noise is small. In the design of preamplifier level are divided into two levels, the first level for common source amplifier circuit, the whole circuit amplification depend mainly on the first level; The second grade level is shot with, ensure tone control circuit has good effect, to the tone control circuit with a small signal source resistance. Tone control mainly is the realization of the input signal is high, the bass ascension and attenuation; Due to the integrated operational amplifier has voltage gain high input impedance, higher advantages, and use it to make the tone of the control circuit has simple structure, stable circuit, etc. Key words: Megaphone; Preamplifier; tone control 目 录 一、设计任务与要求………………………………………………………………4 二、设计原理分析…………………………………………………………………5 2.1 扩音机原理…………………………………………………………………5 2.2 设计思路分析………………………………………………………………5 三、总体设计方案…………………………………………………………………6 3.1 总体方案……………………………………………………………………6 3.1 前置放大器…………………………………………………………………7 3.2 音调控制电路………………………………………………………………7 3.3 有源滤波电路………………………………………………………………9 四、扩音器的调试…………………………………………………………………9 4.1 输入级及音调控制电路的调试……………………………………………9 4.2放大倍数调试………