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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Design and Simulation of Miscellaneous Blocks of an All-Digital PLL for the 60 GHz Band

Butt, Hadiyah, Padala, Manjularani January 2013 (has links)
A phase-locked loop commonly known as PLL is widely used in communication systems. A PLL is used in radio, telecommunications, modulation and demodulation. It can be used for clock generation, clock recovery from data signals, clock distribution and as a frequency synthesizer. Most electronic circuits encounter the problem of the clock skew. The clock Skew for a synchronous circuit is defined as the difference in the time of arrival between two sequentially adjacent registers. The registers and the flip-flops do not receive the clock at the same time. The clock signal in a normal circuit is generated with an oscillator, oscillator produces error, due to which there is a distortion from the expected time interval. The PLLs are used to address the problem. A phase-locked loop works to ensure the time interval seen at the clocks of various registers and the flip-flops match the time intervals generated by the oscillator. PLLs are trivial and an essential part of the micro-processors. Traditional PLLs are designed to work as an analog building block, but it is difficult to integrate them on a digital chip. Analog PLLs are less affected by noise and process variations. Digital PLLs allow faster lock time and are used for clock generation in high performance microprocessors. A digital PLL has more advantages as compared to an analog PLL. Digital PLLs are more flexible in terms of calibration, programability, stability and they are more immune to noise. The cost of a digital PLL is less as compared to its analog counter part. Digital PLLs are analogous to the analog PLLs, but the components used for implementing a digital PLL are digital. A digitally controlled oscillator (DCO) is utilized instead of a voltage controlled oscillator. A time to digital converter(TDC) is used instead of the phase frequency detector. The analog filter is replaced with a digital low pass filter. Phase-locked loop is a very good research topic in electronics. It covers many topics in the electrical systems such as communication theory, control systems and noise characterization. This project work describes the design and simulation of miscellaneous blocks of an all-digital PLL for the 60 GHz band. The reference frequency is 54 MHz and the DCO output frequency is 2 GHz to 3 GHz in a state-of the-art 65 nm process, with 1 V supply voltage. An all-digital PLL is composed of digital components such as a low pass filter, a sigma delta modulator and a fractional N /N +1 divider for low voltage and high speed operation. The all-digital PLL is implemented in MATLAB and then the filter, a sigma delta modulator and a fractional N /N +1 divider are implemented in MATLAB and Verilog-A code. The sub blocks i.e full adder, D flip-flop, a digital to digital converter, a main counter, a prescalar and a swallow counter are implemented in the transistor level using CMOS 65nm technology and functionality of each block is verified.
2

Design of a Time-to-Digital Converter for an All-Digital Phase Locked Loop for the 2-GHz Band

Wali, Naveen, Radhakrishnan, Balamurali January 2013 (has links)
An all-digital phase locked loop for WiGig systems was implemented. The developedall-digital phase locked loop has a targeted frequency range of 2.1-GHz to2.5-GHz. The all-digital phase locked loop replaces the traditional charge pumpbased analog phase locked loop. The digital nature of the all-digital phase lockedloop system makes it superior to the analog counterpart.There are four main partswhich constitutes the all-digital phase locked loop. The time-to-digital converteris one of the important block in all-digital phase locked loop. Several time-to-digital converter architectures were studied and simulated. TheVernier delay based architecture and inverter delay based architecture was designedand evaluated. There architectures provided certain short comings whilethe pseudo-differential time-to-digital converter architecture was chosen, becauseof it’s less occupation of area. Since there exists a relationship between the sizeof the delay cells and it’s time resolution, the pseudo-differential time-to-digitalconverter severed it’s purpose. The whole time-to-digital converter system was tested on a 1 V power supply,reference frequency 54-MHz which is also the reference clock Fref , and a feedbackfrequency Fckv 2.1-GHz. The power consumption was found to be around 2.78mW without dynamic clock gating. When the clock gating or bypassing is done,the power consumption is expected to be reduced considerably. The measuredtime-to-digital converter resolution is around 7 ps to 9 ps with a load variation of15 fF. The inherent delay was also found to be 5 ps. The total output noise powerwas found to be -128 dBm.
3

All-digital Low-power PLL Circuit Design and Load Shift Keying Wireless Modulator Circuit Design for Implantable Biomedical SOC

Tseng, Sheng-lun 04 July 2006 (has links)
The first topic of this thesis is to propose a design of an all-digital low¡Vpower PLL (ADPLL). This design is implemented by only using standard cell library. The design cycle is effectively reduced. Furthermore, the portability and reusability of the proposed design is significantly raised. The large power consumption, glitch hazards, and timing violations of prior ADPLL designs are avoided by the proposed control method and modified DCO with multiplexers. The proposed design is implemented by only using the standard cell library of TSMC (Taiwan Semiconductor Manufacturing Company) 0.18 um 1P6M CMOS process. The feature of power saving is verified by measurement, which shows that the power consumption of the proposed ADPLL is merely 1.45 mW at 166 MHz output. The second topic of this thesis is a load shift keying wireless modulator circuit for implantable biomedical SOC. We successfully realize data and power transmission between outer controller and an implantable chip via wireless RF transmission interface. The convenience and the safety of using the implantable biomedical chip are significantly improved. The proposed on-chip LSK modulator consumes less power and area than those of traditional designs. Hence, the design margin of the implantable biomedical chip will be relaxed. The proposed LSK modulator is implemented with TSMC 0.35um 2P4M mixed-signal process. The proposed wireless RF transmission interface is implemented on PCB with discrete components.
4

Design Techniques for Low Spur Wide Tuning All-Digital Millimeter-Wave Frequency Synthesizers

Hussein, Ahmed 01 February 2017 (has links)
No description available.
5

Design and Implementation of A Personal Gateway for Body Area Networks

Huang, Chi-Chung 12 October 2009 (has links)
In this thesis, we propose a personal gateway for wireless body area network(WBAN). By using wireless communication and a proper WBAN topology, patients¡¦ physiological signal could be recorded without restricting their mobility. Moreover, integration of several kinds of signals from different sensor nodes in one data platform, personal gateway (PG), can reduce the redundant hardware of individual links as well as the complexity of WBAN. A device for long-term bladder urine pressure measurement is designed as a sensor node of PG. Not only is the design cost reduced, but also the reliability is enhanced by using a 1-atm canceling sensing IA (instrumentation amplifier). Because the urine pressure inside the bladder does not vary drastically, both the sleeping and working modes are required to save the battery power for the long-term observation. To integrate circuits with different supply voltages in PG, a 0.9/1.2/1.8/2.5/3.3/5.0 V wide-range I/O buffer carried out using a typical CMOS process is designed. An input buffer with a logic calibration circuit is used for receiving a low voltage signal. A novel floating N-well circuit is employed to remove the body effect at the output PMOS. Moreover, a dynamic driving detector is included to equalize the turn-on voltages for the output PMOS and NMOS transistors. ZigBee is used as a communication channel in this thesis because of its features, including low power, low complexity, medium range, and medium data rate. The 868/915 MHz mode has lower cost and power consumption than those of 2.4 GHz mode, and the data rate is far enough for WBAN applications. Moreover, lower carrier frequency causes less unnecessary power absorbed by human tissue. Therefore, the ZigBee tranceiver with 868/915 MHz mode is explored. A low power all digital phase lock loop (ADPLL) using a controller which employs a binary frequency searching method is also proposed as a clock generator of PG. Glitch hazards and timing violations which occurred very often in prior ADPLLs are avoided by a novel control method and a new digital-controlled oscillator (DCO) with multiplexers. Besides, the feedback DCO is disabled half a cycle in every two cycles so as to reduce 25% of dynamic power theoretically.
6

High-frequency wide-range all digital phase locked loop in 90nm CMOS

Muppala, Prashanth 24 August 2011 (has links)
No description available.
7

Clock Generator Circuits for Low-Power Heterogeneous Multiprocessor Systems-on-Chip

Höppner, Sebastian 14 March 2016 (has links) (PDF)
In this work concepts and circuits for local clock generation in low-power heterogeneous multiprocessor systems-on-chip (MPSoCs) are researched and developed. The targeted systems feature a globally asynchronous locally synchronous (GALS) clocking architecture and advanced power management functionality, as for example fine-grained ultra-fast dynamic voltage and frequency scaling (DVFS). To enable this functionality compact clock generators with low chip area, low power consumption, wide output frequency range and the capability for ultra-fast frequency changes are required. They are to be instantiated individually per core. For this purpose compact all digital phase-locked loop (ADPLL) frequency synthesizers are developed. The bang-bang ADPLL architecture is analyzed using a numerical system model and optimized for low jitter accumulation. A 65nm CMOS ADPLL is implemented, featuring a novel active current bias circuit which compensates the supply voltage and temperature sensitivity of the digitally controlled oscillator (DCO) for reduced digital tuning effort. Additionally, a 28nm ADPLL with a new ultra-fast lock-in scheme based on single-shot phase synchronization is proposed. The core clock is generated by an open-loop method using phase-switching between multi-phase DCO clocks at a fixed frequency. This allows instantaneous core frequency changes for ultra-fast DVFS without re-locking the closed loop ADPLL. The sensitivity of the open-loop clock generator with respect to phase mismatch is analyzed analytically and a compensation technique by cross-coupled inverter buffers is proposed. The clock generators show small area (0.0097mm2 (65nm), 0.00234mm2 (28nm)), low power consumption (2.7mW (65nm), 0.64mW (28nm)) and they provide core clock frequencies from 83MHz to 666MHz which can be changed instantaneously. The jitter performance is compliant to DDR2/DDR3 memory interface specifications. Additionally, high-speed clocks for novel serial on-chip data transceivers are generated. The ADPLL circuits have been verified successfully by 3 testchip implementations. They enable efficient realization of future low-power MPSoCs with advanced power management functionality in deep-submicron CMOS technologies. / In dieser Arbeit werden Konzepte und Schaltungen zur lokalen Takterzeugung in heterogenen Multiprozessorsystemen (MPSoCs) mit geringer Verlustleistung erforscht und entwickelt. Diese Systeme besitzen eine global-asynchrone lokal-synchrone Architektur sowie Funktionalität zum Power Management, wie z.B. das feingranulare, schnelle Skalieren von Spannung und Taktfrequenz (DVFS). Um diese Funktionalität zu realisieren werden kompakte Taktgeneratoren benötigt, welche eine kleine Chipfläche einnehmen, wenig Verlustleitung aufnehmen, einen weiten Bereich an Ausgangsfrequenzen erzeugen und diese sehr schnell ändern können. Sie sollen individuell pro Prozessorkern integriert werden. Dazu werden kompakte volldigitale Phasenregelkreise (ADPLLs) entwickelt, wobei eine bang-bang ADPLL Architektur numerisch modelliert und für kleine Jitterakkumulation optimiert wird. Es wird eine 65nm CMOS ADPLL implementiert, welche eine neuartige Kompensationsschlatung für den digital gesteuerten Oszillator (DCO) zur Verringerung der Sensitivität bezüglich Versorgungsspannung und Temperatur beinhaltet. Zusätzlich wird eine 28nm CMOS ADPLL mit einer neuen Technik zum schnellen Einschwingen unter Nutzung eines Phasensynchronisierers realisiert. Der Prozessortakt wird durch ein neuartiges Phasenmultiplex- und Frequenzteilerverfahren erzeugt, welches es ermöglicht die Taktfrequenz sofort zu ändern um schnelles DVFS zu realisieren. Die Sensitivität dieses Frequenzgenerators bezüglich Phasen-Mismatch wird theoretisch analysiert und durch Verwendung von kreuzgekoppelten Taktverstärkern kompensiert. Die hier entwickelten Taktgeneratoren haben eine kleine Chipfläche (0.0097mm2 (65nm), 0.00234mm2 (28nm)) und Leistungsaufnahme (2.7mW (65nm), 0.64mW (28nm)). Sie stellen Frequenzen von 83MHz bis 666MHz bereit, welche sofort geändert werden können. Die Schaltungen erfüllen die Jitterspezifikationen von DDR2/DDR3 Speicherinterfaces. Zusätzliche können schnelle Takte für neuartige serielle on-Chip Verbindungen erzeugt werden. Die ADPLL Schaltungen wurden erfolgreich in 3 Testchips erprobt. Sie ermöglichen die effiziente Realisierung von zukünftigen MPSoCs mit Power Management in modernsten CMOS Technologien.
8

Clock Generator Circuits for Low-Power Heterogeneous Multiprocessor Systems-on-Chip

Höppner, Sebastian 25 July 2013 (has links)
In this work concepts and circuits for local clock generation in low-power heterogeneous multiprocessor systems-on-chip (MPSoCs) are researched and developed. The targeted systems feature a globally asynchronous locally synchronous (GALS) clocking architecture and advanced power management functionality, as for example fine-grained ultra-fast dynamic voltage and frequency scaling (DVFS). To enable this functionality compact clock generators with low chip area, low power consumption, wide output frequency range and the capability for ultra-fast frequency changes are required. They are to be instantiated individually per core. For this purpose compact all digital phase-locked loop (ADPLL) frequency synthesizers are developed. The bang-bang ADPLL architecture is analyzed using a numerical system model and optimized for low jitter accumulation. A 65nm CMOS ADPLL is implemented, featuring a novel active current bias circuit which compensates the supply voltage and temperature sensitivity of the digitally controlled oscillator (DCO) for reduced digital tuning effort. Additionally, a 28nm ADPLL with a new ultra-fast lock-in scheme based on single-shot phase synchronization is proposed. The core clock is generated by an open-loop method using phase-switching between multi-phase DCO clocks at a fixed frequency. This allows instantaneous core frequency changes for ultra-fast DVFS without re-locking the closed loop ADPLL. The sensitivity of the open-loop clock generator with respect to phase mismatch is analyzed analytically and a compensation technique by cross-coupled inverter buffers is proposed. The clock generators show small area (0.0097mm2 (65nm), 0.00234mm2 (28nm)), low power consumption (2.7mW (65nm), 0.64mW (28nm)) and they provide core clock frequencies from 83MHz to 666MHz which can be changed instantaneously. The jitter performance is compliant to DDR2/DDR3 memory interface specifications. Additionally, high-speed clocks for novel serial on-chip data transceivers are generated. The ADPLL circuits have been verified successfully by 3 testchip implementations. They enable efficient realization of future low-power MPSoCs with advanced power management functionality in deep-submicron CMOS technologies. / In dieser Arbeit werden Konzepte und Schaltungen zur lokalen Takterzeugung in heterogenen Multiprozessorsystemen (MPSoCs) mit geringer Verlustleistung erforscht und entwickelt. Diese Systeme besitzen eine global-asynchrone lokal-synchrone Architektur sowie Funktionalität zum Power Management, wie z.B. das feingranulare, schnelle Skalieren von Spannung und Taktfrequenz (DVFS). Um diese Funktionalität zu realisieren werden kompakte Taktgeneratoren benötigt, welche eine kleine Chipfläche einnehmen, wenig Verlustleitung aufnehmen, einen weiten Bereich an Ausgangsfrequenzen erzeugen und diese sehr schnell ändern können. Sie sollen individuell pro Prozessorkern integriert werden. Dazu werden kompakte volldigitale Phasenregelkreise (ADPLLs) entwickelt, wobei eine bang-bang ADPLL Architektur numerisch modelliert und für kleine Jitterakkumulation optimiert wird. Es wird eine 65nm CMOS ADPLL implementiert, welche eine neuartige Kompensationsschlatung für den digital gesteuerten Oszillator (DCO) zur Verringerung der Sensitivität bezüglich Versorgungsspannung und Temperatur beinhaltet. Zusätzlich wird eine 28nm CMOS ADPLL mit einer neuen Technik zum schnellen Einschwingen unter Nutzung eines Phasensynchronisierers realisiert. Der Prozessortakt wird durch ein neuartiges Phasenmultiplex- und Frequenzteilerverfahren erzeugt, welches es ermöglicht die Taktfrequenz sofort zu ändern um schnelles DVFS zu realisieren. Die Sensitivität dieses Frequenzgenerators bezüglich Phasen-Mismatch wird theoretisch analysiert und durch Verwendung von kreuzgekoppelten Taktverstärkern kompensiert. Die hier entwickelten Taktgeneratoren haben eine kleine Chipfläche (0.0097mm2 (65nm), 0.00234mm2 (28nm)) und Leistungsaufnahme (2.7mW (65nm), 0.64mW (28nm)). Sie stellen Frequenzen von 83MHz bis 666MHz bereit, welche sofort geändert werden können. Die Schaltungen erfüllen die Jitterspezifikationen von DDR2/DDR3 Speicherinterfaces. Zusätzliche können schnelle Takte für neuartige serielle on-Chip Verbindungen erzeugt werden. Die ADPLL Schaltungen wurden erfolgreich in 3 Testchips erprobt. Sie ermöglichen die effiziente Realisierung von zukünftigen MPSoCs mit Power Management in modernsten CMOS Technologien.
9

A Wide Band Adaptive All Digital Phase Locked Loop With Self Jitter Measurement And Calibration

Jiang, Bo 01 January 2016 (has links)
The expanding growth of mobile products and services has led to various wireless communication standards that employ different spectrum bands and protocols to provide data, voice or video communication services. Software deffned radio and cognitive radio are emerging techniques that can dynamically integrate various standards to provide seamless global coverage, including global roaming across geographical regions, and interfacing with different wireless networks. In software deffned radio and cognitive radio, one of the most critical RF blocks that need to exhibit frequency agility is the phase lock loop (PLL) frequency synthesizer. In order to access various standards, the frequency synthesizer needs to have wide frequency tuning range, fast tuning speed, and low phase noise and frequency spur. The traditional analog charge pump frequency synthesizer circuit design is becoming diffcult due to the continuous down-scalings of transistor feature size and power supply voltage. The goal of this project was to develop an all digital phase locked loop (ADPLL) as the alternative solution technique in RF transceivers by taking advantage of digital circuitry's characteristic features of good scalability, robustness against process variation and high noise margin. The targeted frequency bands for our ADPLL design included 880MHz-960MHz, 1.92GHz-2.17GHz, 2.3GHz-2.7GHz, 3.3GHz-3.8GHz and 5.15GHz-5.85GHz that are used by wireless communication standards such as GSM, UMTS, bluetooth, WiMAX and Wi-Fi etc. This project started with the system level model development for characterizing ADPLL phase noise, fractional spur and locking speed. Then an on-chip jitter detector and parameter adapter was designed for ADPLL to perform self-tuning and self-calibration to accomplish high frequency purity and fast frequency locking in each frequency band. A novel wide band DCO is presented for multi-band wireless application. The proposed wide band adaptive ADPLL was implemented in the IBM 0.13µm CMOS technology. The phase noise performance, the frequency locking speed as well as the tuning range of the digitally controlled oscillator was assessed and agrees well with the theoretical analysis.
10

Quantization Effects Analysis on Phase Noise and Implementation of ALL Digital Phase Locked-Loop

Shen, Jue January 2011 (has links)
With the advancement of CMOS process and fabrication, it has been a trend to maximize digital design while minimize analog correspondents in mixed-signal system designs. So is the case for PLL. PLL has always been a traditional mixed-signal system limited by analog part performance. Around 2000, there emerged ADPLL of which all the blocks besides oscillator are implemented in digital circuits. There have been successful examples in application of Bluetooth, and it is moving to improve results for application of WiMax and ad-hoc frequency hopping communication link. Based on the theoretic and measurement results of existing materials, ADPLL has shown advantages such as fast time-to-market, low area, low cost and better system integration; but it also showed disadvantages in frequency resolution and phase noise, etc. Also this new topic still opens questions in many researching points important to PLL such as tracking behavior and quantization effect. In this thesis, a non-linear phase domain model for all digital phase-locked loop (ADPLL) was established and validated. Based on that, we analyzed that ADPLL phase noise prediction derived from traditional linear quantization model became inaccurate in non-linear cases because its probability density of quantization error did not meet the premise assumption of linear model. The phenomena of bandwidth expansion and in-band phase noise decreasing peculiar to integer-N ADPLL were demonstrated and explained by matlab and verilog behavior level simulation test bench. The expression of threshold quantization step was defined and derived as the method to distinguish whether an integer-N ADPLL was in non-linear cases or not, and the results conformed to those of matlab simulation. A simplified approximation model for non-linear integer-N ADPLL with noise sources was established to predict in-band phase noise, and the trends of the results conformed to those of matlab simulation. Other basic analysis serving for the conclusions above covered: ADPLL loop dynamics, traditional linear theory and its quantitative limitations and numerical analysis of random number. Finally, a present measurement setup was demonstrated and the results were analyzed for future work.

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