集成开关电源的数字功放模块的设计

【作者】 张杨；

【导师】 曹宗杰； 李斌；

【作者基本信息】 电子科技大学 ， 电子与通信工程， 2009， 硕士

【摘要】 由于数字音频功放在体积、重量、效率和可靠性等方面比模拟音频功放有明显优势,近年来得到迅速的发展。传统的模拟功放一般采用工频变压器电源和AB类功放,效率低、体积大,笨重,使其应用场合受到很大的限制。本论文将数字音频功放技术和软开关谐振开关电源技术相结合,开发了一款高效率、大功率的数字功放模块。该模块具有高功率密度、高性能指标、自成一体,便于二次开发使用等特点,可以广泛的应用于有源音箱/线性阵列、调音台功放和多通道专业功放等领域。这些都是模拟功放无法实现的。文章简要介绍了数字音频功放的历史、现状以及发展趋势,并对数字功放和开关电源的拓扑结构和原理作了必要的阐述。文中详细介绍了模块的设计过程。其中包括:主要方案的选择、关键元件的选择及参数计算;结构设计和热设计;针对数字音频功放的特点,给出了模块的指标并进行了测试和分析。本论文实现的开关电源和数字音频功放的一体化模块,最大输出功率2000W,重量1.3kg,效率超过80%,信噪比达到116dB,典型失真度0.03%。本论文开发的模块技术指标达到了中高档模拟功放的水平,体积和重量不足相同功率模拟功放的1/3,与国外同类产品技术水平相当,具有市场应用前景。更多还原

【Abstract】 Rapid development of Digital Audio Amplifier (DAA) in recent years mainly benefited from its inherent advantages compared that of Analog Audio Amplifier,such as cubage, weight, efficiency and robustness.Analog Audio Amplifier usually adopts traditional transformer power supply and AB Amplifier, so their low-efficiency, bulky and cumbersome lead great restrictions in many situations.This paper integrates Digital Audio Amplifier technology with switch-mode power supply technology, developed a high efficient and high power Digital Amplifier module. With its high power density, high performance, ease to secondary development, this module will be widely used in in many applications including Active speakers/Line arrays, Amplified mixers, low-cost professional amplifiers and multi-channel amplifiers, all of which never be achieved by Analog Amplifiers.This paper also briefly introduces the history, state-of-art, and future of Digital Audio Amplifier, and then describes the topological structure and principle of digital Amplifier as well as switch-mode power supply.This paper describes the whole design process of the module in details which include tradeoff-making on different schemes and key components, computation of parameters, structure design and thermal design. It also gives key performances of module as well as their measurement and result analysis based on the characteristics of digital amplifiers.This paper realizes a integrate module with a 2000 watt output, 1.3kg weight, 116 dB signal noise radio and 0.03% typical distortion. It also achieves an efficiency more than 80%.The module in this paper has reached the performances of high quality analog Amplifier. With only 1/3 cubage and weight of the same power Analog Audio Amplifier, it has a same level with the similar foreign products, thus it has prospective application in market.更多还原