本論文提出兩種低雜訊功率放大器的設計，在第一個功率放大器中，我們利用回授及低電壓低功率的電路來改善失真及效率。接著我們利用環形振盪器及回授路徑上包含濾波器的概念來完成第二個功率放大器並降低其雜訊。我們經由HSPICE 模擬並使用TSMC 0.35µm ，2P4M CMOS的製程技術來驗證電路的可行性。測量結果顯示了在1.5V的供應電壓下，電路總諧波失真皆低於0.27%，此結果顯示了電路在THD上表現良好，可應用於助聽器驅動器等低雜訊低電壓方面的電路設計。

Two kinds of low distortion switching power amplifiers are presented in this thesis. In the first power amplifier, we use feedback and low voltage low power circuits to improve the distortion and power efficiency. In the second power amplifier, we use ring oscillator and Noise shaping to construct the circuit and filters are added in the feedback loop to reduce the quantization noise. HSPICE simulations and experimental results verify the proposed circuits. Experimental results show that the THDs of both circuits are all lower than 0.27% at 1.5V supply voltage. This result shows that the proposed power amplifiers have superior performance in THD, and these circuits are applicable to low-distortion, high-efficiency, and low-voltage applications, such as the hearing instruments.

Abstract

Chapter 1 Introduction
Chapter 2 Switching Power Amplifier
2.1 The Performance Parameter of Power Amplifiers
2.1.1 Total Harmonic Distortion
2.1.2 Power Efficiency
2.2 Linear Power Amplifiers
2.3 Switching Power Amplifiers
2.3.1 Class D Power Amplifier
2.3.2 Other Switching Power Amplifiers
Chapter 3 The High Efficiency and Low Distortion Switching Power Amplifier
3.1 The Basic Circuit
3.2 Analysis of the Switching Power Amplifier
3.3 Pseudo Differential Amplifier
3.4 Schmitt Trigger
3.5 Switching Frequency
3.6 Output Stage and Low-Pass Filter
3.7 Simulations and Experimental Results
3.7.1 HSPICE Simulation Results
3.7.2 Experimental Results
Chapter 4 The Low Distortion and High Efficiency Self-Oscillating
Power Amplifier
4.1 Intrinsic SOPA Circuit
4.2 The Proposed Power Amplifier
4.3 Simulations and Experimental Results
4.3.1 HSPICE Simulation Results
4.3.2 Experimental Results
Chapter 5 Conclusion
Reference

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