[本科毕业设计] 应用于家庭音响系统的全数字化音频功率放大器

摘要

随着数字音源与数字音频技术的迅速发展，直接对数字音频信号进行功率放大而不需要进行模拟转换(DAC)的数字音频放大器得到了迅速发展，但是在普通的家用音频功率放大器领域却尚未普及数字化，本设计的目的是将全数字化音频功率放大器应用到家庭音响系统中。在众多的全数字功放实现方案中，本系统选用了效果很好的DDX方案，该方案采用DDX信号处理芯片DDX-8001来实现将数字音频的PCM信号转换为数字放大用的DDX（PWM）信号，并用该信号来控制高效的功率器件，不需要为每个声道准备D/A转换器，从而减少了中间不必要的转换层级，音质得到显着的改善，成本也随着零部件数目的减少而下降。本系统完美地实现了从SPDIF格式数字信号输入到声音输出过程中的全数字化处理，达到了高音质、低功耗的效果，实现了全数字家用功放的各种功能，具有较高性能价格比，完全可以适用于普通家庭，具有广阔的应用前景。

关键词数字家庭；数字音频功放；SPDIF信号传输；音频ADC

Abstract

As digital audio and digital audio technology is developing rapidly, the technology of directly amplify the digital audio signal without the DAC is developing very fast, but in the general area of home audio power amplifier is not yet universal digital , The design will take home the all-digital audio power amplifier of the goal. The all-digital amplifier have many solutions, in this case, selected the good effect one，the DDX solution. This solution using the patented DDX signal processing chips DDX-8001 to achieve the PCM digital audio signals convert into the DDX (PWM) signal, and use this signal to control the highly efficient power devices, no need to D/A convert for each channel, thereby reducing the unnecessary middle-level conversion, the sound quality improved significantly, as the number of parts and components reduce the cost drop. The system achieved a high performance when the input is the SPDIF format digital signal , It can achieve a high-quality, low-power all-digital home amplification. So the all-digital home audio power amplifier is an entirely feasible and has a high market value of new products. Moreover, almost all of today's CD/DVD player has SPDIF coaxial or optical digital audio output, signal source not be a problem. This all-digital home audio power amplifier will become the new standard in this area in the near future.

Key words Digital home Digital audio amplifier SPDIF Audio ADC

目录

摘要....................................................................................................................I Abstract...............................................................................................................II 第1章绪论 (1)

1.1 数字功放的研究意义 (1)

1.2 数字功放的研究开发背景 (1)

1.3 国内外现状及发展状态 (1)

1.4本章小结 (2)

第2章系统概述 (3)

2.1 数字功放的设计与选择 (3)

2.2 系统的介绍 (4)

2.3 系统框图 (4)

2.4 系统的功能及特色 (4)

2.5本章小结 (5)

第3章硬件设计 (6)

3.1 数字音频接收设计 (6)

3.1.1芯片概述 (6)

3.1.2配置选择 (6)

3.2 音频ADC的设计 (7)

3.2.1 芯片概述 (7)

3.2.2 ADC配置的选择 (8)

3.3 数字音频数据切换 (10)

3.4 系统的整体控制的设计 (10)

3.4.1控制系统概述 (10)

3.4.2旋转编码器和按键连接电路 (11)

3.4.3背光控制电路 (11)

3.5 电源部分的设计 (12)

3.6 PCB的设计 (13)

3.7本章小结 (14)

第4章软件设计 (15)

4.1 系统程序结构概述 (15)

4.2 对I2C总线的读写及对DDX-8001的控制 (15)

4.2.1 I2C总线基本原理 (15)