臺灣博碩士論文加值系統

摘 要

由於節能省電是目前趨勢，對於可攜式電子產品尤其主要，而音頻放大器的設計、產品應用除了以往講求音質外,未來消費性產品也朝向高效率.省電設計為優先考量，本論文首先介紹傳統音頻放大器Class A/B/AB的結構及特性，並與數位輸出式的音頻放大器Class D作比較,對於Class D的各項特性及優缺點也作詳細說明。

主要內容是探討如何設計Class D的數位輸入調變技術，最後決定3級filter，5 order 6bits SDM（Sigma-Delta Modulation）及PWM來實現電路設計和模擬分析，依據量測值我們觀察是否有達到當初設計的目的或未來可改進的方向。

Abstract

Due to power saving is current trend for portable electronic product and it is very import to design a system. Although audio amplifier design and application focus quality before,but people are leading concern for efficiency to use consumer product now. First, this master thesis introduce traditional audio amplifier structure and characteristic of Class A,B,AB, moreover, we compare with digital input audio amplifier Class D.we also detail various characteristics and advantage of Class D in the preceding chapter.

The major content is discussed how to design a digital input modulator of Class D. We design this digital structure include gain control、3 stage filter、5 order 6 bits sigma-delta modulator and PWM. Per our analysis form actual measurement we have to observe if we achieve original opinion, or not? Maybe we can obtain a way to improve the defects further.

目次

中文摘要 ...........................................................i
英文摘要 ..........................................................ii
目次 .............................................................iii
表目錄 .............................................................v
圖目錄 ............................................................vi
第一章 緒論 ........................................................1
第一節 研究目的 .................................................1
第二節 Class D Amplifier技術介紹 .................................2
第二章 Audio Amplifier 技術 ........................................5
第一節 Class A放大器 ............................................5
第二節Class B放大器 .............................................6
第三節Class AB放大器 ............................................7
第四節Class D 放大器 ............................................7
第五節 Class D放大器的工作原理 ..................................8
第六節 Class D放大器的結構 .....................................11
第七節 Class D放大器的效率 .....................................13
第八節 Class D放大器的失真 .....................................16
第九節 Class D放大器的頻率響應 .................................19
第十節 Class D放大器的電源抑制比（PSSR） .........................19
第十一節 Class D放大器的濾波器 .................................20
第十二節 音頻放大器產品展望 ....................................22
第三章 架構設計及分析 .............................................24
第一節 Digital Class-D技術介紹 .................................24
第二節 Digital Filter介紹 ......................................24
第三節 Sigma-Delta (Σ-Δ) Modulator介紹 ........................27
第四節 PWM Modulator介紹 .......................................28

第四章 範例設計及模擬 .............................................31
第一節 範例設計 ................................................31
第二節 Subwoofer Filter設計 ....................................32
第三節 Gain Control for Anti-Pop設計 ............................33
第四節 Halfband Filter for up sampling設計 .......................34
第五節 PWM Modulator設計 .......................................41
第六節 Sigma-Delta(Σ-Δ) Modulator設計 ..........................41
第七節 Digital Input Class D模擬分析 ............................42
第五章 硬體電路設計與實驗結果 .....................................44
第一節 硬體電路簡介 ............................................44
第二節 USB介面 .................................................45
第三節 Digital Input Class-D FPGA電路 ...........................45
第四節 Gate Driver電路 .........................................56
第五節 實測結果與分析 ..........................................57
第六章 結論與未來研究方向 .........................................60
參考文獻...........................................................61

參考文獻

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