臺灣博碩士論文加值系統

　　本論文設計一個直流轉直流降壓切換式穩壓器，使其具備高轉換效率及快速暫態響應，適用於可攜式電子產品，例如：手機、數位相機、PDA等等。

　　為了提高功率轉換效率，採用PFM及PWM雙控制模式，分別運用在輕載及重載的情況下。此外還加入零電流偵測器，防止在輕載時發生逆電流，減少不必要的功率消耗。另外也設計軟啟動裝置，消除在最初啟動時，可能會對功率級元件造成損傷的過大電流。為了改善暫態響應，此系統加入一個快速暫態控制器以降低回復時間，使得當負載電流從15mA上升至600mA時，電壓回復時間從原本的33μs降至12μs，提升反應速度。最後，整體效率最高可達到94%。

　　此穩壓器是使用台灣積體電路製造股份有限公司所提供的0.35μm 2P4M 3.3V/5V Mixed Signal CMOS製程技術來設計與製造，整體晶片面積大約為1.5*1.5mm2。

　　The design of a DC-DC buck switching regulator for high power conversion efficiency and fast transient response is presented in this thesis. It is suitable for portable electronic applications powered by batteries such as mobile phone, digital camera, PDA, etc.

　　To make power conversion more efficient, the regulator uses PFM and PWM dual control mode, for light load and heavy load condition, respectively. In addition, a zero current detector is used to reduce the unnecessary power consumption in light load. Furthermore, in order to eliminate the excess large current at the start up of the regulator that may damage the device of the power stage, the soft start circuit is designed. For improving the transient response, a fast transient controller is added to this system to reduce the transient response recovery time. Compared with the original circuit, the recovery time is reduced from 33μs to 12μs when load current suddenly changes from 15mA to 600mA. The dynamic response is effectively improved. Finally, the conversion efficiency could be up to 94%.

　　The regulator is designed and fabricated with TSMC 0.35μm 2P4M 3.3V/5V Mixed Signal CMOS technology. The chip size is about 1.5*1.5mm2.

誌謝 I
摘要 II
Abstract III
目錄 IV
圖目錄 VII
表目錄 X
第一章 緒論 1
1.1 背景 1
1.2 研究動機 1
1.3 論文架構 2
第二章 電源轉換器概論 3
2.1 切換式穩壓器的規格 3
2.1.1輸出漣波 3
2.1.2線性穩壓 3
2.1.3負載穩壓 3
2.1.4溫度穩壓 4
2.1.5暫態響應 4
2.1.6效率 6
2.2 轉換器種類及原理 7
2.2.1降壓式轉換器(Buck Converter) 7
2.2.2升壓型轉換器(Boost Converter) 10
2.2.3升降壓轉換器(Buck-Boost Converter) 12
2.3 非連續導通模式(The Discontinuous Conduction DCM) 14
2.3.1降壓型轉換器(Buck Converter) 15
2.3.2升壓型轉換器(Boost Converter) 16
2.3.3升降壓轉換器(Buck-Boost Converter) 17
2.4 同步整流技術 18
2.5 切換式電源轉換器的控制方式 20
2.5.1電壓模式脈波寬度調變(Voltage-Mode PWM) 20
2.5.2電流模式脈波寬度調變(Current-Mode PWM) 21
2.5.3脈波頻率調變(PFM) 25
2.6 系統迴路穩定度分析 26
2.6.1誤差放大器的補償電路 28
第三章 電路設計與模擬 31
3.1 整體系統架構 31
3.2 功率級(Power Stage) 32
3.3 能隙參考電壓(Bandgap Voltage Reference Circuit) 32
3.4 偏壓電路(Bias Circuit) 35
3.5 比較器(Comparator) 35
3.6 脈波及鋸齒波產生器(Oscillator and Ramp Generator) 36
3.7 電壓/電流轉換器(V-I Converter) 37
3.8 緩衝電路(Buffer) 39
3.9 零電流偵測器(Zero Current Detector) 40
3.10 電流感測電路(Current Sensing Circuit) 41
3.11 PFM/PWM 偵測選擇器(PFM/PWM Detector) 42
3.12 PWM調變器(PWN Modulator) 43
3.13 PFM控制器(PFM Controller) 43
3.14 軟啟動電路(Soft Start Circuit) 44
3.15 快速暫態控制器(Fast-Transient Controller) 45
3.16 多工器(Mux) 46
第四章 系統模擬與佈局 47
4.1 軟啟動 47
4.2 脈波頻率調變模擬 49
4.2.1線性穩壓 49
4.2.2負載穩壓 49
4.3 電流模式脈波寬度調變模擬 50
4.3.1線性穩壓 50
4.3.2負載穩壓 51
4.4 暫態響應 52
4.5 效率 54
4.6 電路效能總表 55
4.7 實體佈局及量測圖 55
第五章 結論 60
參考文獻 61

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