CMOS Optical Preamplifier Design Using Graphical Circuit Analysis

More documents

Recommendations

Info

2.3 Transimpedance Amplifier Design Requirements 16 2.3 TRANSIMPEDANCE AMPLIFIER DESIGN REQUIREMENTS Traditionally, the design challenge of fiber-optic preamplifiers has been in optimizing the trade-offs between sensitivity, speed, and transimpedance gain. As dis- cussed in the previous chapter, new applications of optical communications have introduced additional receiver requirements such as wide dynamic range, ambient light rejection, and low-voltage operation. This section discusses each of these requirements in greater detail, and reviews previously reported solutions. 2.3.1 Wide Dynamic Range C T Figure 2.6 Optical preamplifier based on a transimpedance amplifier. R f A wide dynamic range is essential in order to accommodate variable link distances. Current IrDA standards, for instance, require an optical dynamic range of 51dB in order to support a link distances range of 0 cm up to 100 cm[IrDA,1997]. Although the dynamic range of a transimpedance amplifier is greater than that of a high-impedance design, it is still insufficient to handle such a wide input range. As illustrated in Figure 2.7, there are three principal techniques for extending the dynamic range of the preamplifier: 1) output signal limiting, 2) input current steering, and 3) variable transimpedance gain. i s v s -A v out
2.3 Transimpedance Amplifier Design Requirements 17 The simplest technique is to limit the output swing as represented by the diode clamp in Figure 2.7. While limiting does not affect the lower limit of the dynamic range, it does increase the upper limit by allowing the receiver to accept strong sig- nals that would have otherwise overloaded the receiver and prevented normal operation. Limiting can be performed either within the preamplifier [Yamazaki,1997], or in cases where the dynamic range requirements are more modest, externally by fol- lowing the preamplifier with a limiter circuit [Nakamura,1999], [Ohhata,1999]. The advantage of limiting is that it does not require level detection circuitry. However, the process of limiting destroys the amplitude information of the received signal. As such, limiting can only be used with binary signalling schemes. In addition, limiting introduces pulse width distortions that result out of the uneven gain applied to dif- ferent portions of the pulse. Finally, for applications in which ambient light is an issue, limiting removes information that helps separate the ambient light from the information signal. 2 I tail V ctl Level Detection Figure 2.7 Various methods of increasing dynamic range: 1) output signal limiting, 2) input current steering, and 3) variable transimpedance gain. The second technique, input current steering, also improves the dynamic range by increasing the maximum acceptable signal level of the preamplifier. It uses a dif- R f r f 1 3
Page 1 and 2: CMOS Optical Preamplifier Design Us
Page 3 and 4: To achieve low-voltage operation, w
Page 5 and 6: Table of Contents CHAPTER 1 INTRODU
Page 7 and 8: CHAPTER 1 1.1 OVERVIEW Introduction
Page 9 and 10: Information Source Modulator Drive
Page 11 and 12: 1.2 Thesis Outline 5 [Ohhata,1999].
Page 13 and 14: 1.2 Thesis Outline 7 technique call
Page 15 and 16: 1.2 Thesis Outline 9 Detector in St
Page 17 and 18: E e + - V bias 2.1 Photodetectors 1
Page 19 and 20: Diode Capacitance (pF) Diode capaci
Page 21: 2.2 Optical Preamplifier Structures
Page 25 and 26: 2.3 Transimpedance Amplifier Design
Page 27 and 28: I dc 2.3 Transimpedance Amplifier D
Page 29 and 30: 2.3 Transimpedance Amplifier Design
Page 31 and 32: Source Figure 2.11 General structur
Page 33 and 34: A = = For = 1V , the solution is v
Page 35 and 36: The gain of the forward amplifier c
Page 37 and 38: Feedback Analysis Using Return Rati
Page 39 and 40: 2.4 Circuit Analysis Techniques 33
Page 41 and 42: 2.5 An Overview of Signal-Flow Grap
Page 43 and 44: 1 x1 x2 2.5 An Overview of Signal-F
Page 45 and 46: 2.6 SUMMARY REFERENCES • ∆ k =
Page 47 and 48: Symp. Circuits Systems, vol. 3, pp.
Page 49 and 50: CHAPTER 3 New Transimpedance Amplif
Page 51 and 52: 3.1 A Differential Transimpedance A
Page 57 and 58: 3.2 A Feedback Topology for Ambient
Page 59 and 60: 3.2 A Feedback Topology for Ambient
Page 61 and 62: Transimpedance (dBΩ) 90 80 60 40
Page 63 and 64: 3.3 A Low-Voltage Transimpedance Am
Page 73 and 74:
C 3 Φ1VB M 3 V B- =0.7V M 7 Figure
Page 75 and 76:
3.3 A Low-Voltage Transimpedance Am
Page 77 and 78:
3.4 SUMMARY 3.4 Summary 71 In this
Page 79 and 80:
3.4 Summary 73 Y. Nakagome et al.,
Page 81 and 82:
4.1 Introduction 75 back topology o
Page 83 and 84:
4.2 Circuit Analysis Using Driving-
Page 85 and 86:
Page 87 and 88:
Page 89 and 90:
Page 91 and 92:
4.3 DPI/SFG: Combining DPI Analysis
Page 93 and 94:
4.4 Determining Port Impedances 87
Page 95 and 96:
v i R in v o R out 4.4 Determining
Page 97 and 98:
id » ro and 1 ⁄ rid « Av ⁄ ro
Page 99 and 100:
Page 101 and 102:
Page 103 and 104:
Z b r e g m 4.5 Analyzing Transisto
Page 105 and 106:
4.5 Analyzing Transistor Circuits 9
Page 107 and 108:
Figure 4.25 SFG for the source foll
Page 109 and 110:
Page 111 and 112:
Page 113 and 114:
Page 115 and 116:
5.1 Analysis of the Low-Voltage Tra
Page 117 and 118:
5.1 Analysis of the Low-Voltage Tra
Page 119 and 120:
5.2 DEVELOPING AN ANALYTIC CIRCUIT
Page 121 and 122:
Z in 5.2 Developing an Analytic Cir
Page 123 and 124:
5.2 Developing an Analytic Circuit
Page 125 and 126:
I n1 : i in I n2 -I n1 i scin ( sCi
Page 127 and 128:
Page 129 and 130:
I nRf : 5.2 Developing an Analytic
Page 131 and 132:
DC transimpedance gain: Pole locati
Page 133 and 134:
Frequency (MHz) 500 450 400 350 300
Page 135 and 136:
Pole frequencies(MHz) 500 450 400 3
Page 137 and 138:
Optimizing Sensitivity 5.2 Developi
Page 139 and 140:
Page 141 and 142:
Transimpedance Volts dB (lin) Gain
Page 143 and 144:
CHAPTER 6 Implementation and Experi
Page 145 and 146:
6.1 A 1V Optical Receiver Front-End
Page 147 and 148:
Page 149 and 150:
6.1.2 Experimental Results 6.1 A 1V
Page 151 and 152:
Gain(dB) 0 −1 −2 −3 −4 −5
Page 153 and 154:
Page 155 and 156:
Page 157 and 158:
Page 159 and 160:
Clock signal of voltage doubler Eye
Page 161 and 162:
6.2 Variable-Gain Transimpedance Am
Page 163 and 164:
6.2.2 Experimental Results 6.2 Vari
Page 165 and 166:
6.3 Summary and State-of-the-Art Co
Page 167 and 168:
Reference Outputs Technology Supply
Page 169 and 170:
CHAPTER 7 Conclusions 7.1 SUMMARY A
Page 171 and 172:
7.2 Future Work 165 The significanc
Page 173 and 174:
7.2 Future Work 167 supply and subs
Page 175 and 176:
v s i ti that part of the SFG for Q
Page 177 and 178:
Thus, P1 ′ = b = 500Ω ∆1 ′
Page 179 and 180:
itive representation of circuit dyn
Page 181 and 182:
Bipolar Transistor i scb Z b v b b
show all

CMOS Optical Preamplifier Design Using Graphical Circuit Analysis

Create successful ePaper yourself

Delete template?

Save as template?