【作者】 李莹莹；

【导师】 陈宝远；

【作者基本信息】 哈尔滨理工大学 ， 电子与通信工程， 2015， 硕士

【摘要】 随着电子技术和数字信号处理技术的发展，音频功率放大器的发展也进入了一个新的时代，数字功率放大器相对于模拟功放具有高效率、保真度高、功放和扬声器的匹配好等优点，但目前应用较为广泛的数字音频功放为PWM(脉冲宽度调制)功放结构，它在将信号解调的过程中，会产生误差，同时信号的输出波形不够平滑，噪声较高，对信号的恢复程度较弱。针对此类问题，本文采用以DSP为核心设计的数字音频功率放大器模块，利用内插算法和调制算法实现1比特激励信号的输出，替代传统的PWM转化过程。同原有的PWM数字化设计方式相比，本方案可以减小失真，降低噪声，在高音质输出方面有较好的设计效果。本文是对数字音频大功率放大系统的设计及研究，适用于广场、会议室等场合，具有对音频系统及音频效果需求较高的特点。结合现阶段数字功率放大器的相关技术及未来的发展动态，针对课题需求，应用DSP实现数字功放的1比特激励信号，并配合相应的外围电路，完成系统的供电、保护等模块的设计。结合系统设计需求，选择一款合适的核心处理器，TI公司的67XX系列DSP以其在数字信号处理上的优势和先进的芯片性能可以比较容易的实现该设计的主要功能，完成系统中重要的内插和调制模块，并可以通过其丰富的外设接口完成数据的输入和输出。开发过程中利用TI的软件开发平台CCS组织DSP系统的软件结构，并通过CCS观察和验证算法在DSP内的实现情况。论文阐述了系统方案的设计目的及任务，研究了1比特技术的相关算法，完成了各模块电路的硬件设计及软件设计，并对音频输出信号进行分析，完成系统整体性能测试，最后总结系统设计的总体情况，提出了设计的相关改进工作和项目发展方向。更多还原

【Abstract】 With the development of electronic technology and digital signal processingtechnology, audio power amplifier has entered a new era, the development ofdigital power amplifier compared with analog power amplifier with highefficiency and good fidelity, power amplifier and speakers as well as good match,but the widely used digital audio amplifier is the PWM (pulse width modulation)power amplifier structure, it is in the process of signal demodulation, willproduce ineviTab. error, at the same time the output of the signal waveform is notsmoth, high noise, and the signal recovery degree is weak.For such problems, this paper adopts DSP as the core design of the digitalaudio power amplifier module, using the interpolation and the output of theexcitation signal modulation algorithm1bit, instead of traditional PWMconversion process. Compared with the original way of PWM digital design, thisscheme can reduce the distortion and noise, also has good design effect in highquality output.Power amplifier design in this paper is mainly used in square, conferenceroom and so on demand for speech signal amplifier and signal effect of thepursuit of more occasions. Based on the relevant technology of digital poweramplifier at present stage and future development trends, demand for subject,using DSP digital power amplifier of1bit excitation signal, and combined withthe corresponding peripheral circuits, completed the design of power supply andprotection module for the system.Combining with the design requirement of system, choose a suiTab. coreprocessor, the67xx series DSP of company called TI, with its advantages indigital signal processing and advanced chip performance can be relatively easy tothe realization of the main function in this design, complete the importantinterpolation and modulation module in the system. And can be done through its abundant peripheral interface of input an output data. During the developmentprocess, using the platform for CCS of TI design the software strcture of DSPsystem, and by observation of CCS and validation algorithm in DSP.This paper introduce in detail the design idea of system platform, completedthe design of each module, and do the simulation algorithm for system, putsforward the concrete method of using DSP to produce excitation signal. Finally,summarizes the process of the project, put forward the need to improve the workand the development direction of the project.更多还原