캘리브레이션이 필요없는 위상고정 루프의 설계

학위논문 (박사)-- 서울대학교 대학원 : 전기·컴퓨터공학부, 2017. 2. 김재하.A PVT-insensitive-bandwidth PLL and a chirp frequency synthesizer PLL are proposed using a constant-relative-gain digitally-controlled oscillator (DCO), a constant-gain time-to-digital converter (TDC), and a simple digital loop filter (DLF) without an explicit calibration or additional circuit components. A digital LC-PLL that realizes a PVT-insensitive loop bandwidth (BW) by using the constant-relative-gain LC-DCO and constant-gain TDC is proposed. In other words, based on ratiometric circuit designs, the LC-DCO can make a fixed percent change to its frequency for a unit change in its digital input and the TDC can maintain a fixed range and resolution measured in reference unit intervals (UIs) across PVT variations. With such LC-DCO and TDC, the proposed PLL can realize a bandwidth which is a constant fraction of the reference frequency even with a simple proportional-integral digital loop filter without any explicit calibration loops. The prototype digital LC-PLL fabricated in a 28-nm CMOS demonstrates a frequency range of 8.38~9.34 GHz and 652-fs,rms integrated jitter from 10-kHz to 1-GHz at 8.84-GHz while dissipating 15.2-mW and occupying 0.24-mm^2. Also, the PLL across three different die samples and supply voltage ranging from 1.0 to 1.2V demonstrates a nearly constant BW at 822-kHz with the variation of ±4.25-% only. A chirp frequency synthesizer PLL (FS-PLL) that is capable of precise triangular frequency modulation using type-III digital LC-PLL architecture for X-band FMCW imaging radar is proposed. By employing a phase-modulating two-point modulation (TPM), constant-gain TDC, and a simple second-order DLF with polarity-alternating frequency ramp estimator, the PLL achieves a gain self-tracking TPM realizing a frequency chirp with fast chirp slope (=chirp BW/chirp period) without increasing frequency errors around the turn-around points, degrading the effective resolution achievable. A prototype chirp FS-PLL fabricated in a 65nm CMOS demonstrates that the PLL can generate a precise triangular chirp profile centered at 8.9-GHz with 940-MHz bandwidth and 28.8-us period with only 1.9-MHz,rms frequency error including the turn-around points and 14.8-mW power dissipation. The achieved 32.63-MHz/us chirp slope is higher than that of FMCW FS-PLLs previously reported by 2.6x.CHAPTER 1 INTRODUCTION 1 1.1 MOTIVATION 1 1.2 THESIS ORGANIZATION 5 CHAPTER 2 CONVENTIONAL PHASE-LOCKED LOOP 7 2.1 CHARGE-PUMP PLL 7 2.1.1 OPERATING PRINCIPLE 7 2.1.2 LOOP DYNAMICS 9 2.2 DIGITAL PLL 10 2.2.1 OPERATING PRINCIPLE 11 2.2.2 LOOP DYNAMICS 12 CHAPTER 3 VARIATIONS ON PHASE-LOCKED LOOP 14 3.1 OSCILLATOR GAIN VARIATION 14 3.1.1 RING VOLTAGE-CONTROLLED OSCILLATOR 15 3.1.2 LC VOLTAGE-CONTROLLED OSCILLATOR 17 3.1.3 LC DIGITALLY-CONTROLLED OSCILLATOR 19 3.2 PHASE DETECTOR GAIN VARIATION 20 3.2.1 LINEAR PHASE DETECTOR 20 3.2.2 LINEAR TIME-TO-DIGITAL CONVERTER 21 CHAPTER 4 PROPOSED DCO AND TDC FOR CALIBRATION-FREE PLL 23 4.1 DIGTALLY-CONTROLLED OSCILLATOR (DCO) 25 4.1.1 OVERVIEW 24 4.1.2 CONSTANT-RELATIVE-GAIN DCO 26 4.2 TIME-TO-DIGITAL CONVERTER (TDC) 28 4.2.1 OVERVIEW 28 4.2.2 CONSTANT-GAIN TDC 30 CHAPTER 5 PVT-INSENSITIVE-BANDWIDTH PLL 35 5.1 OVERVIEW 36 5.2 PRIOR WORKS 37 5.3 PROPOSED PVT-INSENSITIVE-BANDWIDTH PLL 39 5.4 CIRCUIT IMPLEMENTATION 41 5.4.1 CAPACITOR-TUNED LC-DCO 41 5.4.2 TRANSFORMER-TUNED LC-DCO 45 5.4.3 OVERSAMPLING-BASED CONSTANT-GAIN TDC 49 5.4.4 PHASE DIGITAL-TO-ANALOG CONVERTER 52 5.4.5 DIGITAL LOOP FILTER 54 5.4.6 FREQUENCY DIVIDER 55 5.4.7 BANG-BANG PHASE-FREQUENCY DETECTOR 56 5.5 CELL-BASED DESIGN FLOW 57 5.6 MEASUREMENT RESULTS 58 CHAPTER 6 CHIRP FREQUENCY SYNTHESIZER PLL 66 6.1 OVERVIEW 67 6.2 PRIOR WORKS 71 6.3 PROPOSED CHIRP FREQUENCY SYNTHESIZER PLL 75 6.4 CIRCUIT IMPLEMENTATION 83 6.4.1 SECOND-ORDER DIGITAL LOOP FILTER 83 6.4.2 PHASE MODULATOR 84 6.4.3 CONSTANT-GAIN TDC 85 6.4.4 VRACTOR-BASED LC-DCO 87 6.4.5 OVERALL CLOCK CHAIN 90 6.5 MEASUREMENT RESULTS 91 6.6 SIGNAL-TO-NOISE RATIO OF RADAR 98 CHAPTER 7 CONCLUSION 100 BIBLIOGRAPHY 102 초록 109Docto

Architecture and Control of a Digital Frequency-Locked Loop for Fine-Grain Dynamic Voltage and Frequency Scaling in Globally Asynchronous Locally Synchronous Structures

International audienceA small area fast-reprogrammable Digital Frequency-Locked Loop (DFLL) engine is presented as a solution for the Dynamic Voltage and Frequency Scaling (DVFS) circuitry in Globally Asynchronous Locally Synchronous (GALS) architectures implemented in 32 nm CMOS technology. The DFLL control is designed so that the closed-loop system is able to cope with process variability while it rejects temperature changes and supply voltage slow variations. Therefore the DFLL is made of three main blocks, namely a Digitally Controlled Oscillator (DCO), a "sensor" that measures the frequency of the signal at the output of the DCO and a controller. A strong emphasis is set on the loop filter architecture choice and the tuning of its parameters. An analytical model of the DCO is deduced from accurate Spice simulations. The delay introduced by the sensor is also taken into account to design. From these models, an optimal and robust controller with a minimum implementation area is developed. Here, "optimal" means that the controller is computed via the minimization of a given criterion while the "robustness" capability ensures that the closed-loop system is tolerant to process and temperature variations in a given range. Therefore, performances of the closed-loop system are ensured whatever the system characteristics are in a given range

차량용 CIS Interface 를 위한 All-Digital Phase-Locked Loop 의 설계 및 분석

학위논문 (석사) -- 서울대학교 대학원 : 공과대학 전기·정보공학부, 2021. 2. 정덕균.This thesis presents design techniques for All-Digital Phase-Locked Loop (ADPLL) assisting the automotive CMOS image sensor (CIS) interface. To target Gear 3 of the automotive physical system, the proposed AD-PLL has a wide operation range, low RMS jitter, and high PVT tolerance characteristics. Detailed analysis of the loop dynamics and the noise analysis of AD-PLL are done by using Matlab and Verilog behavioral modeling simulation before an actual design. Based on that analysis, the optimal DLF gain configurations are yielded, and also, accurate output responses and performance are predictable. The design techniques to reduce the output RMS jitter are discussed thoroughly and utilized for actual implementation. The proposed AD-PLL is fabricated in the 40 nm CMOS process and occupies an effective area of 0.026 mm2. The PLL output clock pulses exhibit an RMS jitter of 827 fs at 2 GHz. The power dissipation is 5.8 mW at 2 GHz, where the overall supply voltage domain is 0.9 V excluding the buffer which is 1.1 V domain.본 논문에서는 자동차 CMOS 이미지 센서 (CIS) 인터페이스를 지원하 는 AD-PLL 을 제안한다. Automotive Physical 시스템의 Gear 3 를 지원하기 위해 제안된 AD-PLL 은 1.5 GHz 에서 3 GHz 의 동작 주파수를 가지며, 낮 은 RMS Jitter 및 PVT 변화에 대한 높은 둔감성을 갖는다. 설계에 앞서서 Matlab 및 Verilog Behavioral Simulation 을 통해 Loop system 의 역학에 대한 자세한 분석 및 AD-PLL 의 Noise 분석을 수행하였고, 이 분석을 기반으로 최적의 DLF gain 과 정확한 출력 응답 및 성능을 예측 할 수 있었다. 또한, 출력의 Phase Noise 와 RMS Jitter 를 줄이기 위한 설계 기법을 자세히 다루고 있으며 이를 실제 구현에 활용했다. 제안된 회로는 40 nm CMOS 공정으로 제작되었으며 Decoupling Cap 을 제외하고 0.026 mm2 의 유효 면적을 차지한다. 측정된 출력 Clock 신호의 RMS Jitter 값은 2 GHz 에서 827 fs 이며, 총 5.8 mW의 Power 를 소비한다. 이 때, 전체적인 공급 전압은 0.9 V 이며, Buffer 의 Power 만이 1.1 V 를 사용하 였다.ABSTRACT I CONTENTS II LIST OF FIGURES IV LIST OF TABLES VII CHAPTER 1 INTRODUCTION 1 1.1 MOTIVATION 1 1.2 THESIS ORGANIZATION 3 CHAPTER 2 BACKGROUND ON ALL-DIGITAL PLL 4 2.1 OVERVIEW 4 2.2 BUILDING BLOCKS OF AD-PLL 7 2.2.1 TIME-TO-DIGITAL CONVERTER 7 2.2.2 DIGITALLY-CONTROLLED OSCILLATOR 10 2.2.3 DIGITAL LOOP FILTER 13 2.2.4 DELTA-SIGMA MODULATOR 16 2.3 PHASE NOISE ANALYSIS OF AD-PLL 20 2.3.1 BASIC ASSUMPTION OF LINEAR ANALYSIS 20 2.3.2 NOISE SOURCES OF AD-PLL 21 2.3.3 EFFECTS OF LOOP DELAY ON AD-PLL 24 2.3.4 PHASE NOISE ANALYSIS OF PROPOSED AD-PLL 26 CHAPTER 3 DESIGN OF ALL-DIGITAL PLL 28 3.1 DESIGN CONSIDERATION 28 3.2 OVERALL ARCHITECTURE 30 3.3 CIRCUIT IMPLEMENTATION 32 3.3.1 PFD-TDC 32 3.3.2 DCO 37 3.3.3 DIGITAL BLOCK 43 3.3.4 LEVEL SHIFTING BUFFER AND DIVIDER 45 CHAPTER 4 MEASUREMENT AND SIMULATION RESULTS 52 4.1 DIE PHOTOMICROGRAPH 52 4.2 MEASUREMENT SETUP 54 4.3 TRANSIENT ANALYSIS 57 4.4 PHASE NOISE AND SPUR PERFORMANCE 59 4.4.1 FREE-RUNNING DCO 59 4.4.2 PLL PERFORMANCE 61 4.5 PERFORMANCE SUMMARY 65 CHAPTER 5 CONCLUSION 67 BIBLIOGRAPHY 68 초 록 72Maste

A Bang-Bang All-Digital PLL for Frequency Synthesis

abstract: Phase locked loops are an integral part of any electronic system that requires a clock signal and find use in a broad range of applications such as clock and data recovery circuits for high speed serial I/O and frequency synthesizers for RF transceivers and ADCs. Traditionally, PLLs have been primarily analog in nature and since the development of the charge pump PLL, they have almost exclusively been analog. Recently, however, much research has been focused on ADPLLs because of their scalability, flexibility and higher noise immunity. This research investigates some of the latest all-digital PLL architectures and discusses the qualities and tradeoffs of each. A highly flexible and scalable all-digital PLL based frequency synthesizer is implemented in 180 nm CMOS process. This implementation makes use of a binary phase detector, also commonly called a bang-bang phase detector, which has potential of use in high-speed, sub-micron processes due to the simplicity of the phase detector which can be implemented with a simple D flip flop. Due to the nonlinearity introduced by the phase detector, there are certain performance limitations. This architecture incorporates a separate frequency control loop which can alleviate some of these limitations, such as lock range and acquisition time.Dissertation/ThesisM.S. Electrical Engineering 201

고속 시리얼 링크를 위한 고리 발진기를 기반으로 하는 주파수 합성기

학위논문(박사) -- 서울대학교대학원 : 공과대학 전기·정보공학부, 2022. 8. 정덕균.In this dissertation, major concerns in the clocking of modern serial links are discussed. As sub-rate, multi-standard architectures are becoming predominant, the conventional clocking methodology seems to necessitate innovation in terms of low-cost implementation. Frequency synthesis with active, inductor-less oscillators replacing LC counterparts are reviewed, and solutions for two major drawbacks are proposed. Each solution is verified by prototype chip design, giving a possibility that the inductor-less oscillator may become a proper candidate for future high-speed serial links. To mitigate the high flicker noise of a high-frequency ring oscillator (RO), a reference multiplication technique that effectively extends the bandwidth of the following all-digital phase-locked loop (ADPLL) is proposed. The technique avoids any jitter accumulation, generating a clean mid-frequency clock, overall achieving high jitter performance in conjunction with the ADPLL. Timing constraint for the proper reference multiplication is first analyzed to determine the calibration points that may correct the existent phase errors. The weight for each calibration point is updated by the proposed a priori probability-based least-mean-square (LMS) algorithm. To minimize the time required for the calibration, each gain for the weight update is adaptively varied by deducing a posteriori which error source dominates the others. The prototype chip is fabricated in a 40-nm CMOS technology, and its measurement results verify the low-jitter, high-frequency clock generation with fast calibration settling. The presented work achieves an rms jitter of 177/223 fs at 8/16-GHz output, consuming 12.1/17-mW power. As the second embodiment, an RO-based ADPLL with an analog technique that addresses the high supply sensitivity of the RO is presented. Unlike prior arts, the circuit for the proposed technique does not extort the RO voltage headroom, allowing high-frequency oscillation. Further, the performance given from the technique is robust over process, voltage, and temperature (PVT) variations, avoiding the use of additional calibration hardware. Lastly, a comprehensive analysis of phase noise contribution is conducted for the overall ADPLL, followed by circuit optimizations, to retain the low-jitter output. Implemented in a 40-nm CMOS technology, the frequency synthesizer achieves an rms jitter of 289 fs at 8 GHz output without any injected supply noise. Under a 20-mVrms white supply noise, the ADPLL suppresses supply-noise-induced jitter by -23.8 dB.본 논문은 현대 시리얼 링크의 클락킹에 관여되는 주요한 문제들에 대하여 기술한다. 준속도, 다중 표준 구조들이 채택되고 있는 추세에 따라, 기존의 클라킹 방법은 낮은 비용의 구현의 관점에서 새로운 혁신을 필요로 한다. LC 공진기를 대신하여 능동 소자 발진기를 사용한 주파수 합성에 대하여 알아보고, 이에 발생하는 두가지 주요 문제점과 각각에 대한 해결 방안을 탐색한다. 각 제안 방법을 프로토타입 칩을 통해 그 효용성을 검증하고, 이어서 능동 소자 발진기가 미래의 고속 시리얼 링크의 클락킹에 사용될 가능성에 대해 검토한다. 첫번째 시연으로써, 고주파 고리 발진기의 높은 플리커 잡음을 완화시키기 위해 기준 신호를 배수화하여 뒷단의 위상 고정 루프의 대역폭을 효과적으로 극대화 시키는 회로 기술을 제안한다. 본 기술은 지터를 누적 시키지 않으며 따라서 깨끗한 중간 주파수 클락을 생성시켜 위상 고정 루프와 함께 높은 성능의 고주파 클락을 합성한다. 기준 신호를 성공적으로 배수화하기 위한 타이밍 조건들을 먼저 분석하여 타이밍 오류를 제거하기 위한 방법론을 파악한다. 각 교정 중량은 연역적 확률을 기반으로한 LMS 알고리즘을 통해 갱신되도록 설계된다. 교정에 필요한 시간을 최소화 하기 위하여, 각 교정 이득은 타이밍 오류 근원들의 크기를 귀납적으로 추론한 값을 바탕으로 지속적으로 제어된다. 40-nm CMOS 공정으로 구현된 프로토타입 칩의 측정을 통해 저소음, 고주파 클락을 빠른 교정 시간안에 합성해 냄을 확인하였다. 이는 177/223 fs의 rms 지터를 가지는 8/16 GHz의 클락을 출력한다. 두번째 시연으로써, 고리 발진기의 높은 전원 노이즈 의존성을 완화시키는 기술이 포함된 주파수 합성기가 설계되었다. 이는 고리 발진기의 전압 헤드룸을 보존함으로서 고주파 발진을 가능하게 한다. 나아가, 전원 노이즈 감소 성능은 공정, 전압, 온도 변동에 대하여 민감하지 않으며, 따라서 추가적인 교정 회로를 필요로 하지 않는다. 마지막으로, 위상 노이즈에 대한 포괄적 분석과 회로 최적화를 통하여 주파수 합성기의 저잡음 출력을 방해하지 않는 방법을 고안하였다. 해당 프로토타입 칩은 40-nm CMOS 공정으로 구현되었으며, 전원 노이즈가 인가되지 않은 상태에서 289 fs의 rms 지터를 가지는 8 GHz의 클락을 출력한다. 또한, 20 mVrms의 전원 노이즈가 인가되었을 때에 유도되는 지터의 양을 -23.8 dB 만큼 줄이는 것을 확인하였다.1 Introduction 1 1.1 Motivation 3 1.1.1 Clocking in High-Speed Serial Links 4 1.1.2 Multi-Phase, High-Frequency Clock Conversion 8 1.2 Dissertation Objectives 10 2 RO-Based High-Frequency Synthesis 12 2.1 Phase-Locked Loop Fundamentals 12 2.2 Toward All-Digital Regime 15 2.3 RO Design Challenges 21 2.3.1 Oscillator Phase Noise 21 2.3.2 Challenge 1: High Flicker Noise 23 2.3.3 Challenge 2: High Supply Noise Sensitivity 26 3 Filtering RO Noise 28 3.1 Introduction 28 3.2 Proposed Reference Octupler 34 3.2.1 Delay Constraint 34 3.2.2 Phase Error Calibration 38 3.2.3 Circuit Implementation 51 3.3 IL-ADPLL Implementation 55 3.4 Measurement Results 59 3.5 Summary 63 4 RO Supply Noise Compensation 69 4.1 Introduction 69 4.2 Proposed Analog Closed Loop for Supply Noise Compensation 72 4.2.1 Circuit Implementation 73 4.2.2 Frequency-Domain Analysis 76 4.2.3 Circuit Optimization 81 4.3 ADPLL Implementation 87 4.4 Measurement Results 90 4.5 Summary 98 5 Conclusions 99 A Notes on the 8REF 102 B Notes on the ACSC 105박

Techniques for Frequency Synthesizer-Based Transmitters.

Internet of Things (IoT) devices are poised to be the largest market for the semiconductor industry. At the heart of a wireless IoT module is the radio and integral to any radio is the transmitter. Transmitters with low power consumption and small area are crucial to the ubiquity of IoT devices. The fairly simple modulation schemes used in IoT systems makes frequency synthesizer-based (also known as PLL-based) transmitters an ideal candidate for these devices. Because of the reduced number of analog blocks and the simple architecture, PLL-based transmitters lend themselves nicely to the highly integrated, low voltage nanometer digital CMOS processes of today. This thesis outlines techniques that not only reduce the power consumption and area, but also significantly improve the performance of PLL-based transmitters.PhDElectrical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/113385/1/mammad_1.pd

Designing an Ultralow-Voltage Phase-Locked Loop Using a Bulk-Driven Technique

[[abstract]]This brief describes an ultralow-voltage phase-locked loop (PLL) using a bulk-driven technique. The architecture of the proposed PLL employs the bulk-input technique to produce a voltage-controlled oscillator (VCO) and the forward-body-bias scheme to produce a divider. This approach effectively reduces the threshold voltage of the MOSFETs, enabling the PLL to be operated at an ultralow voltage. The chip is fabricated in a 0.13-mum standard CMOS process with a 0.5-V power supply voltage. The measurement results demonstrate that this PLL can operate from 360 to 610 MHz with a 0.5-V power supply voltage. At 550 MHz, the measured root-mean-square jitter and peak-to-peak jitter are 8.01 and 56.36 ps, respectively. The total power consumption of the PLL is 1.25 mW, and the active die area of the PLL is 0.04 mm2.[[notice]]補正完畢[[incitationindex]]SCI[[incitationindex]]EI[[booktype]]紙

12???14.5 GHZ DIGITALLY CONTROLLED OSCILLATOR USING A HIGH-RESOLUTION DELTA-SIGMA DIGITAL-TO-ANALOG CONVERTER

Department of Electrical EngineeringThis thesis focuses on the design of digitally-controlled oscillators (DCO) for ultra-low-jitter digital phase-locked-loops (PLL), which requires very fine frequency resolution and low phase noise performance. Before going details of the design, fundamentals of the digital-to-analog converter (DAC), delta-sigma modulator (DSM), LC voltage-controlled oscillator (VCO) are discussed in Chapters 2, 3, and 4 respectively. Detailly, Chapter 2 begins with the basic operations of the digital-toanalog converters. Plus, several types of DACs and their properties are discussed. For instance, resistorbased DAC or current source-based DAC. In Chapter 3, the backgrounds of DSMs are presented. The reason why DSMs are indispensable components in fractional number generation is presented. The meaning of the randomization and noise shaping in DSMs is discussed then high-order noise shaping DSMs are explained as well. Chapter 4, starts with the LC tanks. Integrated passive components are introduced such as spiral inductors, metal-insulator-metal (MIM) capacitors, and metal-oxide-metal (MOM) capacitors. The start-up of the oscillators also explained by using two approaches, the Barkhausen criterion and the negative resistance theory. Then the pros and cons of the CMOS and NMOS type topologies are stated. Finally, the phase noise in oscillators is analyzed by using the Leeson???s equation and the impulse-sensitivity function theory. In chapter 5, the detailed designs of the prototype DCO are presented. The designed DCO consists of 2nd order DSM, string resistor-based DAC, and CMOS-type LC VCO. The frequency resolutions of the proportional and integral path are different but the structures are identical. For the high-performance oscillator, iterative design is required. In the measurements, the designed DCO achieved 17 and 18 bit of frequency resolution in the proportional and integral path respectively, 12-14.5GHz of the frequency tuning range, 50 and 500MHz/V of KVCO for the main and auxiliary loop respectively, and -184.5 dB of figure of merit (FOM). The power consumption is 5.5mW and the prototype was fabricated in TSMC 65nm CMOS process.clos