Nanometer Frequency Synthesis Beyond the Phase-Locked Loop

1 CLOCK SIGNAL IN ELECTRONIC SYSTEMS 1
1.1 The Significance of Clock Signal 1
1.2 The Characteristics of Clock Signal 5
1.3 Clock Signal Driving Digital System 18
1.4 Clock Signal Driving Sampling System 24
1.5 Extracting Clock Signal From Data: Clock Data Recovery 30
1.6 Clock Usage in System-on-Chip 32
1.7 Two Fields: Clock Generation and Clock Distribution 33

2 CLOCK GENERATION: EXISTING FREQUENCY SYNTHESIS TECHNIQUES 37
2.1 Direct Analog Frequency Synthesis 38
2.2 Direct Digital Frequency Synthesis 39
2.3 Indirect Method (Phase-Locked Loop Based) 41
2.4 The Shared Goal: All Cycles Have Same Length-in-Time 51

3 TIME-AVERAGE-FREQUENCY 53
3.1 The Scale of Level and the Scale of Time 53
3.2 What Is Frequency? 54
3.3 Reinvestigating the Frequency Concept: the Birth of Time-Average-Frequency 56
3.4 Time-Average-Frequency in Circuit Implementation 59
3.5 Average Frequency, Time-Average-Frequency, and Fundamental Frequency 61
3.6 The Need of a Theory 62
3.7 The Summary: Why Do We Need Time-Average-Frequency? 63

4 FLYING-ADDER DIRECT PERIOD SYNTHESIS ARCHITECTURE 65
4.1 The Working Principle 65
4.2 The Major Challenges in the Flying-Adder Circuit 68
4.3 The Circuit of Proof of Concept 74
4.4 The Working Circuitry 77
4.5 Frequency Transfer Function, Frequency Range, Frequency Resolution, and Frequency Switching Speed 87
4.6 The Technique of Post Divider Fractional Bits Recovery 88
4.7 Flying-Adder PLL: FAPLL 90
4.8 Flying-Adder Fractional Divider 91
4.9 Integer-Flying-Adder Architecture 92
4.10 The Algorithm to Search Optimum Parameters 98
4.11 The Construction of the Accumulator 99
4.12 The Construction of the High Speed Multiplex 104
4.13 Non-2's Power Flying-Adder Circuit 107
4.14 Expanding VCO Frequency Range in Nanometer CMOS Processes 109
4.15 Multiple Flying-Adder Synthesizers 110
4.16 Flying-Adder Implementation Styles 111
4.17 Simulation Approaches 112
4.18 The Impact of Input Mismatch on Output Jitter 113
4.19 Flying-Adder Circuit as Digital Controlled Oscillator 127
4.20 Flying-Adder Terminology 128
4.21 Flying-Adder Synthesizer and Time-Average-Frequency: The Experimental Evidence 129
4.22 Time-Average-Frequency and Setup Constraint: Revisit 154
4.23 Sense the Frequency Difference: The Time-Average-Frequency Way 156
4.24 Flying-Adder and Direct Digital Synthesis (DDS): The Difference 157
4.25 Flying-Adder for Phase (Delay) Synthesis 158
4.26 Flying-Adder for Duty Cycle Control 162
4.27 Flying-Adder Synthesizer in Reducing the Number of PLLs in SoC 163

5 DIGITAL-TO-FREQUENCY CONVERTER 167
5.1 Two Ways of Representing Information 167
5.2 The Converters for Transforming Information 168
5.3 The Two Cornerstones of the Digital-to-Frequency Converter 170
5.4 The Theoretical Foundation of Flying-Adder Digital-to-Frequency Converter 172
5.5 Convert the Spurious Energy to Noise Energy 193
5.6 Move Spurs Around 198
5.7 Spread the Energy 201
5.8 Performance Merits 205

6 THE NEW FRONTIER IN ELECTRONIC SYSTEM DESIGN 211
6.1 The Clocking Challenges in Reality 211
6.2 Flying-Adder and Its Three Major Application Areas 216
6.3 Flying-Adder for On-chip Frequency Generation 218
6.4 Flying-Adder as Adaptive Clock Generator 222
6.5 Flying-Adder as On-chip VCXO 230
6.6 Flying-Adder for Frame Rate Synchronization and Display Monitor Accommodation 237
6.7 Flying-Adder for Frequency Synchronization in Digital Communication: A Preview 240
6.8 Flying-Adder for Clock Data Recovery 242
6.9 Flying-Adder DLL for Deskew 255
6.10 Flying-Adder for Digital Frequency-Locked Loop (Flying-Adder DFLL) 256
6.11 Flying-Adder for Digital Phase-Locked Loop (Flying-Adder DPLL) 262
6.12 Flying-Adder Technology for Dynamic Frequency Scaling 262
6.13 Flying-Adder as 1-bit DDFS 264
6.14 Flying-Adder for Spread Spectrum Clocking 265
6.15 Flying-Adder for Driving Sampling System 268
6.16 Flying-Adder for Non-uniform Sampling 271
6.17 Flying-Adder as Digital FSK Modulator 273
6.18 Flying-Adder for PWM/PFW DC-DC Power Conversion 274
6.19 Integrate Clocking Chips into Processing Chips 275

7 LOOKING INTO FUTURE: THE ERA OF "TIME" 279
7.1 The Four Fundamental Technologies in Modern Chip Design 279
7.2 "Time"-Based Analog Processing 281
7.3 "Time" and Frequency: Encoding Messages Through Modulation 283
7.4 Manipulate "Time": The Tools 283
7.5 It Is Time to Use "Time" 284

APPENDICES 287
Appendix 4.A: The VHDL Code for Flying-Adder Synthesizer 287
Appendix 4.B: How Close Can It Reach an Integer? 296
Appendix 4.C: The Seed and Set in Integer-Flying-Adder PLL 299
Appendix 4.D: The Number of Carries From an XIU-Accumulator 302
Appendix 5.A: The Flying-Adder State Machine Model (perl) 303
Appendix 5.B: The Flying-Adder Waveform Generator (perl) 307
Appendix 5.C: The Flying-Adder Waveform Generator with Triangular Modulation (perl) 310
Appendix 5.D: The Flying-Adder Waveform Generator with Random Modulation (perl) 314
Appendix 6.A: The FA-DCXO Tangent Line and Linearity Measurement 318

INDEX 321