臺灣博碩士論文加值系統

為了因應多功能攜帶裝置的發展，系統上晶片(System on Chip)以及三維晶片(3D IC)被廣泛應用於整合不同功能之電路於同一晶片上，藉此發展出更輕薄的行動裝置，若是將傳統的切換式降壓轉換器使用在這樣的系統上，藉由輸出電流操作範圍廣以及暫態速度快等特點，能夠對各個不同之電路進行最佳之電源管理設計。然而，卻會因為外接的電感與電容造成整合上的不方便，因此本論文的目標就是將傳統的外接電感與電容一併整合至晶片上，增加整體系統的整合性，本論文介紹與分析整合電感電容濾波器之切換式直流降壓轉換器設計。整合電感電容濾波器因為品質不佳造成轉換效率的衰減，並且在晶片上會佔據大量面積，本論文推導了最佳化之式子以便將切換式轉換器設計至理想之工作點，這些式子可應用於一個簡單的設計流程，並幫助設計者在有限的條件與環境下得到理想的結果。我們也實際把所謂的疊接交錯結構應用在一個設計原型之中，藉此電感電流相消之技術將整體之面積做更進一步的壓縮。此設計原型是在0.18微米製程下實現一個完全整合之切換式直流降壓轉換器，電壓轉換比例為3.3伏特至1.8伏特，晶片中共使用了兩個10奈亨利的電感與總共3.55奈法拉的電容，最後量測結果達到了最高48.27％的轉換效率與100毫伏特之輸出電壓波動。

histhesisintroducestheanalysisanddesignofaDC-DCbuckconverterwithanintegratedLClter.Theon-chipinductorandcapacitorcauseeciencydegra-dationandmuchareacost.Wederivetheoptimizedequationsforndingouttheoptimaloperatingpointoftheswitchingconverter.Theseequationscanbeappliedforasimpledesign
owtogetcompromisingresultsbetweendesignspec-icationsandconstraints.Astackedinterleavedstructureisadoptedinournaldesignprototypetoprovidetheinductor-currentcancellationwhichmakewholechipcompact.ItisafullyintegratedDC-DCconverterina0.18-mtechnology.Thevoltageconversionratioisinputof3.3Vtooutputof1.8V.Themeasuredresultshowsourdesignhasmaximumeciencyof48.27%withtwoinductorsof10nHandtotaloutputcapacitanceof3.55nF.LastRevised:July,20,2011

1 Introduction 1
1.1 Introduction and Motivation 1
1.2 Thesis Organization 2
2 DC-DC Buck Converter with On-Chip LC Filter 3
2.1 Basic DC-DC Buck Converter 3
2.2 Fully-Integrated Buck Converter 6
2.2.1 Efficiency Estimation 7
2.2.2 Optimization Procedure 8
2.2.3 Analysis and Discussion 9
2.3 Design Flow 12
3 Inductor-Current Ripple Cancelling Techniques 16
3.1 Interleaved Topology 16
3.1.1 Standard Interleaved Topology 17
3.1.2 Stacked Interleaved Topology 18
3.2 Topology Comparison 21
3.2.1 Efficiency Performance 21
3.2.2 Output-Voltage Ripple Performance 24
3.3 Modified Design Flow 28
4 System Design and Circuit Implementation 30
4.1 Control Scheme 30
4.1.1 Voltage Mode 30
4.1.2 Current Mode 31
4.1.3 V 2 Control 32
4.1.4 Hysteretic Control and the Modified Control Method 33
4.2 System Design 35
4.2.1 System Parameter and Design 35
4.2.2 Loop Transfer Function 38
4.3 Circuit Implementation 41
4.3.1 Error Amplifier 42
4.3.2 Hysteretic Comparator 44
4.3.3 Non-Overlapping Circuit, Level Shifter and Driver 46
4.3.4 Output Capacitors 46
4.3.5 Simulation Result 48
5 Measurement Result 51
6 Conclusion 56

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