臺灣博碩士論文加值系統

中文摘要

由於CPU的能量消耗日益增加，多相數的電壓調整器需要符合現今高效率在主機板上之要求，本論文應用相位展頻裝置在主機板上之CPU電源模組，進而設計十六相式直流降壓電源轉換器。一般而言，在控制器的設計上，較多相數及多組的PWM輸出是需要的。因此，發展一個非常多相數的PWM 控制器變得非常有挑戰性，並且需要很多的針腳數包裝，也就造成了高成本及複雜的佈局。
本論文使用一個相位展頻裝置，將一個PWM訊號展成兩個相差180度角的PWM訊號，藉此達到八相式展至十六相式的目的，以克服上述之問題。論文本身也詳細分析了十六相式能量消耗的效率模擬，並以實驗結果證實依據負載狀況使用切相裝置，能在低負載時降低相數，高負載時提升相數，進而減少損失並提升效率。

ABSTRACT
As the power consumption of microprocessors increase, a multi-phase voltage regulator is required to meet the power hunger and high efficiency requirements. In this thesis, in order to design and implementation of a 16 phase DC/DC buck converter, phase extender is applied on the power module of CPU on the motherboard. In general, the higher the phase number count, the more PWM outputs are required for the PWM controller. Consequently, developing a multi-phase PWM controller becomes very challenging and requires a high pin count package, resulting in high cost and complex layout design.
In this thesis, the IC of the phase extender is applied, and which can extend a PWM signal to two interleaved PWM signals. As a result, the purpose of extending 8 phases to 16 phases is achieved, and that can overcome the above mentioned problems. Moreover, the efficiency simulation of 16 phases power consumption is analyzed in this thesis, and the experimental results are provided. In order to reduce the phase numbers in the low loading, enhance the phase numbers in the high loading, lower power consumption and increase the efficiency, the phase shedding is used according to the loading.

TABLE OF CONTENTS
Page
ACKNOWLEDGEMENTS i
CHINESE ABSTRACT ii
ENGLISH ABSTRACT iii
TABLE OF CONTENTS iv
LIST OF FIGURES vii
LIST OF TABLES x
CHAPTER
1. INTRODUCTON 1
1.1 Motivation and Background 1
1.2 The Purpose of the Study 5
2. SYNCHRONOUS RECTIFICATION PRINCIPLE 6
2.1 Buck Circuit Operation 6
2.2 Continuous Mode 7
2.3 Synchronous Buck Converter 12
2.4 Output Voltage Ripple 13
2.5 Effects of Comportments on Efficiency 14

3. THE STABLE COMPENSATION NETWORK FOR VOLTAGE MODE 17
3.1 Stable Compensation Networks for Voltage Mode 17
3.2 PWM Modulator 18
3.3 Output Filter 19
3.4 Open Loop System 20
3.5 Compensation Network 23
3.6 Closed Loop with Compensation Network 28
4. THE MULTI-PHASE BUCK CONVERTER 32
4.1 Multi-phase Buck Converter 32
4.2 Current Sharing Scheme and DCR Sense 34
4.3 Phase Doubler 36
4.3.1 Single Phase 36
4.3.2 Multi-Phase 36
4.3.3 Phase Extender 38
4.3.4 Feedback Doubler 40
4.4 Power Loss Analysis in Multiphase Voltage Regulator 42
5. MEASUREMENT OF MULTI-PHASE BUCK CONVERTER 48
5.1 Phase Extender Application Circuit 48
5.2 Experimental Data for 16 Phase System 49
5.3 Reduced Output Ripple Current and Voltage 50
5.4 Improved Efficiency by Phase Shedding 53
6. CONCLUSIONS AND FUTURE STUDIES 55
6.1 Conclusions 55
6.2 Future Studies 56
REFERENCES 57

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