臺灣博碩士論文加值系統

近年來低電壓的電路系統需求日益增加，尤其對於系統單晶片的應用更加的明顯。當我們把工作電壓降低，數位電路將能在相同的電路效能下擁有更小的功率消耗；但是對於類比電路而言，整體電路的效能將會受到很大的影響。除此之外，電路的面積將需要被適當的考量，以降低進階多功能式系統單晶片的成本。因此，新穎的類比積體電路技術將是個非常熱門的課題。
新穎的轉導放大器以及無線與有線系統的應用將被介紹於此篇論文。轉導放大器為類比電路中基本的建構方塊。通常此放大器將應用於轉導電容式濾波器、連續時間三角積分調變器、壓控震盪器以及乘法器。首先，我們設計了兩種工作於高速的轉導放大器。於此設計當中，於奈米技術所產生的短通道效應將被討論與消除。結果驗證了此電路將能於高速下維持非常好的效能。
接下來我們討論了一廣泛可調頻寬式的轉導電容式濾波器。此濾波器使用了五階的elliptic形式並設計於非常低的截止頻寬。經由切換電阻的方式，此濾波器將能工作於生醫系統、音訊系統以及部分的無線系統。結果證明了在可調頻寬範圍內，此電路的線性度將能被適當的維持。
三種應用於直接轉換接收器之多模通道選擇濾波器被介紹於此篇論文當中。這些濾波器將涵蓋了2G (GSM)、3G(cdma2000與Wideband CDMA)、藍芽(buletooth)與無線區域網路(IEEE 802.11 a/b/g/n Wireless LANs)。我們依照規格設計特定的轉導放大器，並經由三階的elliptic濾波器的形式加以實現。所設計的結果驗證符合所需的無線系統規範。
最後，兩種高速的濾波器被報告於此篇論文。此高速濾波器接使用了四階equiripple濾波器的形式，以使用於脈衝訊號系統當中。其中之一的濾波器設計於硬碟(HDD)存取系統。同時先進的自動校正電路將被實現，此電路將用來抵抗製程與溫度所產生的變異。另外的濾波器將應用於超寬頻(UWB)系統，經由適當的設計，此電路能工作於低電壓源。

There are growing demands for low-supply circuits and systems. This is especially true for system-on-a-chip application. Switching to use lower power supply voltage, digital circuits do not suffer the degradation of their performances too much. On the other hand, for analog circuits, the circuit performances are strongly affected by the low voltage supply. In addition, the chip area should also be taken into consideration to reduce large costs of advanced multi-function SOC design. Therefore, new design techniques for analog circuits are required to be developed.
In this research work, novel transconductors with the applications to wireless and wireline systems are introduced. The transconductor is a basic building block for analog circuits, such as the Gm-C filter, continuous-time delta sigma modulator, voltage controlled oscillator and multiplier. Two transconductors working at high frequency is developed at first. The short channel effects in the nano-scale technology are discussed and eliminated, and the results show the high performance even at high speed operation.
A wide tuning range Gm-C filter with a 5th-order Elliptic prototype for very low frequency is discussed. Through the use of switching technology, the filter can operate from the biomedical systems and the audio systems to part of wireless systems. The distortion performance maintained over the tuning range is also shown.
Three multi-mode channel section filters for the Zero-IF direct conversion receiver are presented. These filters cover the wireless applications of GSM, bluetooth, cdma2000, wideband CDMA and IEEE 802.11 a/b/g/n Wireless LANs. The specific transconductors with required function are designed. Through the use of a 3th-order Butterworth prototype, the results are shown to meet the specifications of various wireless applications.
Two high speed filters with a 4th-order equiripple prototype are presented. The high speed filter can be used for pulse signal systems. One is designed for the hard disk storage systems. A novel automatic tuning circuit is also implemented to account for process and temperature variations. The other is designed for the UWB system. This circuit can work well under a low supply voltage.

Contents


Abstract
Acknowledgements
List of Tables
List of Figures
1 Motivation 1
1.1 Introduction 1
1.2 Applications 2
1.3 Organization 3
2 Transconductor 4
2.1 Introduction 4
2.2 A review of CMOS transconductor 4
2.2.1 The source degenerated transconductor 4
2.2.2 The constant drain-source transconductor 7
2.2.3 The pseudo-differential transconductor 9
2.2.4 The floating-gate transconductor 11
2.3 A 40MHz double differential-pair CMOS OTA with -60dB IM3 14
2.3.1 Introduction 14
2.3.2 Nonlinearity analysis of saturated MOS transistors 15
2.3.2.1 The floating-gate transconductor 15
2.3.2.2 Saturated MOS transistor in nano-Scale CMOS technology 15
2.3.2.3 Design methodology 18
2.3.3 Proposed OTA circuit 21
2.3.3.1 Implementation of linearization technique 21
2.3.3.2 The common-mode stability 22
2.3.4 Non-ideality analysis of the implementation 24
2.3.4.1 Mismatch 24
2.3.4.2 Thermal noise 24
2.3.5 Experimental results 25
2.3.6 Summary 28
2.3 A 1-V 50MHz pseudo-differential OTA with compensation of the mobility reduction 28
2.4.1 Introduction 29
2.4.2 The proposed transconductor cell 30
2.4.2.1 Mobility compensation 30
2.4.2.2 Proposed OTA implementation 34
2.4.2.3 Nonidealities in the proposed OTA 36
2.4.3 Experimental results 38
2.4.4 Summary 38
3 Gm-C Filter 40
3.1 Introduction 40
3.2 The implementation of the Gm-C filter 40
3.2.1 Integrator 40
3.2.2 Programmable integrator 44
3.2.3 Filter synthesis methods 45
3.2.3.1 Biqued sections 46
3.2.3.2 Signal flow graph 48
3.2.4 Effect of integrator non-idealities in filter 52
3.2.4.1 Non-zero output conductance 52
3.2.4.2 Parasitic poles and zeros 53
3.2.4.3 Noise 55
3.2.4.4 Dynamic range performance 57
3.2.4.4.1 Total harmonic distortion (THD) 57
3.2.4.4.2 The third-order intercept point (IP3) 59
3.2.4.4.3 Spurious-free dynamic range (SFDR) 61
3.3 A wide tuning range Gm-C continuous-time analog filter 62
3.3.1 Introduction 62
3.3.2 The proposed transconductor cell 63
3.3.2.1 Implementation of Linearization Technique 63
3.3.2.1.1 The transconductor cell operating in the weak inversion region 64
3.3.2.1.2 The transconductor cell operating in the strong inversion region 66
3.3.2.1.3 The transconductor cell operating in the multi-inversion regions 69
3.3.2.2 Noise analysis of the proposed transconductor 70
3.3.3 The equivalent resistor REQ 71
3.3.3.1 Switching methodology 71
3.3.3.1.1 Bias current condition 73
3.3.3.1.2 Linearity and noise analyses 86
3.3.4 Filter architecture 77
3.3.5 Experimental results 81
3.3.6 Summary 85
4 Multi-mode channel selection filter for wireless applications 87
4.1 Introduction 87
4.2 Zero-IF receiver 87
4.3 A Gm-C continuous-time analog filter for multi-mode wireless applications 88
4.3.1 Introduction 88
4.3.2 Proposed transconductor circuit 89
4.3.3 The equivalent resistor and the CMFB circuit 90
4.3.3.1 The equivalent resistor 90
4.3.3.2 The CMFB circuit 92
4.3.4 Filter Architecture 93
4.3.5 Results 95
4.3.6 Summary 95
4.4 Multi-mode Gm-C channel selection filter for mobile applications in 1-V supply voltage 96
4.4.1 Introduction 97
4.4.2 Proposed transconductor circuit 98
4.4.2.1 The triode region MOS characteristic 98
4.4.2.2 The transconductor implementation 99
4.4.2.3 The high linearity current multiplier 101
4.4.2.4 The CMFB circuit 103
4.4.3 Filter architecture and measurement result 104
4.4.4 Summary 105
4.5 A wide tuning range Gm-C filter for multi-mode direct-conversion wireless receivers 106
4.5.1 Introduction 106
4.5.2 Proposed transconductor circuit 107
4.5.2.1 The voltage-to-current conversion in CMOS technology 108
4.5.2.2 The proposed transconductor with tuning scheme 110
4.5.2.3 The final circuit implementation 113
4.5.2.4 Nonidealities in the proposed circuit 115
4.5.3 Filter architecture and measurement results 117
4.5.4 Summary 120
5 High speed filter with the automatic tuning circuit 121
5.1 Introduction 121
5.2 Linear phase filter 122
5.2.1 Filter transfer function 122
5.2.2 Group delay sensitivity 123
5.3 Automatic tuning circuit 125
5.3.1 Direct tuning architecture 125
5.3.2 Indirect tuning architecture 126
5.4 A 1 GHz equiripple low-pass filter with a high-speed automatic tuning scheme 129
5.4.1 Introduction 130
5.4.2 Operational transconductance amplifier 130
5.4.2.1 The voltage-to-current conversion 130
5.4.2.2 The common-mode control system 132
5.4.2.3 Gain enhancement and trancsonductance tuning circuit 133
5.4.3 Filter architecture and automatic tuning circuit 134
5.4.4 Measurement results 137
5.4.5 Summary 139
5.5 A 1-V Gm-C low-pass filter for UWB wireless application 140
5.5.1 Introduction 140
5.5.2 Proposed operational transconductance amplifier 141
5.4.3 Common-mode control circuit 144
5.4.4 Filter implementation and measurement results 145
5.4.5 Summary 148
6 Conclusions 150
Bibliography 151
Vita 159

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