Author: Siew Ching YipPublisher:
ISBN:
Category :
Languages : en
Pages : 94
Book Description
Design and Analysis of Analog Cmos Voltage Control Oscillator (vco)
Author: Siew Ching YipDesign of High-Performance CMOS Voltage-Controlled Oscillators
Author: Liang DaiPublisher: Springer Science & Business Media
ISBN: 1461511453
Category : Technology & Engineering
Languages : en
Pages : 170
Book Description
Design of High-Performance CMOS Voltage-Controlled Oscillators presents a phase noise modeling framework for CMOS ring oscillators. The analysis considers both linear and nonlinear operation. It indicates that fast rail-to-rail switching has to be achieved to minimize phase noise. Additionally, in conventional design the flicker noise in the bias circuit can potentially dominate the phase noise at low offset frequencies. Therefore, for narrow bandwidth PLLs, noise up conversion for the bias circuits should be minimized. We define the effective Q factor (Qeff) for ring oscillators and predict its increase for CMOS processes with smaller feature sizes. Our phase noise analysis is validated via simulation and measurement results. The digital switching noise coupled through the power supply and substrate is usually the dominant source of clock jitter. Improving the supply and substrate noise immunity of a PLL is a challenging job in hostile environments such as a microprocessor chip where millions of digital gates are present.
Design of VCO-based ADCs
Author: Vishnu UnnikrishnanPublisher: Linköping University Electronic Press
ISBN: 9176856240
Category :
Languages : en
Pages : 52
Book Description
Today's complex electronic systems with billions of transistors on a single die are enabled by the aggressive scaling down of the device feature size at an exponential rate as predicted by the Moore's law. Digital circuits benefit from technology scaling to become faster, more energy efficient as well as more area efficient as the feature size is scaled down. Moreover, digital design also benefits from mature CAD tools that simplify the design and cross-technology porting of complex systems, leveraging on a cell-based design methodology. On the other hand, the design of analog circuits is getting increasingly difficult as the feature size scales down into the deep nanometer regime due to a variety of reasons like shrinking voltage headroom, reducing intrinsic gain of the devices, increasing noise coupling between circuit nodes due to shorter distances etc. Furthermore, analog circuits are still largely designed with a full custom design ow that makes their design and porting tedious, slow, and expensive. In this context, it is attractive to consider realizing analog/mixed-signal circuits using standard digital components. This leads to scaling-friendly mixed-signal blocks that can be designed and ported using the existing CAD framework available for digital design. The concept is already being applied to mixed-signal components like frequency synthesizers where all-digital architectures are synthesized using standard cells as basic components. This can be extended to other mixed-signal blocks like digital-to-analog and analog to- digital converters as well, where the latter is of particular interest in this thesis. A voltage-controlled oscillator (VCO)-based analog-to-digital converter (ADC) is an attractive architecture to achieve all-digital analog-to digital conversion due to favorable properties like shaping of the quantization error, inherent anti-alias filtering etc. Here a VCO operates as a signal integrator as well as a quantizer. A converter employing a ring oscillator as the VCO lends itself to an all-digital implementation. In this dissertation, we explore the design of VCO-based ADCs synthesized using digital standard cells with the long-term goal of achieving high performance data converters built from low accuracy switch components. In a first step, an ADC is designed using vendor supplied standard cells and fabricated in a 65 nm CMOS process. The converter delivers an 8-bit ENOB over a 25 MHz bandwidth while consuming 3.3 mW of power resulting in an energy efficiency of 235 fJ/step (Walden FoM). Then we utilize standard digital CAD tools to synthesize converter designs that are fully described using a hardware description language. A polynomial-based digital post-processing scheme is proposed to correct for the VCO nonlinearity. In addition, pulse modulation schemes like delta modulation and asynchronous sigma-delta modulation are used as a signal pre-coding scheme, in an attempt to reduce the impact of VCO nonlinearity on converter performance. In order to investigate the scaling benefits of all-digital data conversion, a VCO-based converter is designed in a 28 nm CMOS process. The design delivers a 13.4-bit ENOB over a 5 MHz bandwidth achieving an energy efficiency of 4.3 fJ/step according to post-synthesis schematic simulation, indicating that such converters have the potential of achieving good performance in deeply scaled processes by exploiting scaling benefits. Furthermore, large conversion errors caused by non-ideal sampling of the oscillator phase are studied. An encoding scheme employing ones counters is proposed to code the sampled ring oscillator output into a number, which is resilient to a class of sampling induced errors modeled by temporal reordering of the transitions in the ring. The proposed encoding reduces the largest error caused by random reordering of up to six subsequent bits in the sampled signal from 31 to 2 LSBs. Finally, the impact of process, voltage, and temperature (PVT) variations on the performance while operating the converter from a subthreshold supply is investigated. PVT-adaptive solutions are suggested as a means to achieve energy-efficient operation over a wide range of PVT conditions.
Low Power VCO Design in CMOS
Author: Marc TieboutPublisher: Springer Science & Business Media
ISBN: 354029256X
Category : Technology & Engineering
Languages : en
Pages : 126
Book Description
This work covers the design of CMOS fully integrated low power low phase noise voltage controlled oscillators for telecommunication or datacommuni- tion systems. The need for low power is obvious, as mobile wireless telecommunications are battery operated. As wireless telecommunication systems use oscillators in frequency synthesizers for frequency translation, the selectivity and signal to noise ratio of receivers and transmitters depend heavily on the low phase noise performance of the implemented oscillators. Datacommunication s- tems need low jitter, the time-domain equivalent of low phase noise, clocks for data detection and recovery. The power consumption is less critical. The need for multi-band and multi-mode systems pushes the high-integration of telecommunication systems. This is o?ered by sub-micron CMOS feat- ing digital ?exibility. The recent crisis in telecommunication clearly shows that mobile hand-sets became mass-market high-volume consumer products, where low-cost is of prime importance. This need for low-cost products - livens tremendously research towards CMOS alternatives for the bipolar or BiCMOS solutions in use today.
Microelectronics, Electromagnetics and Telecommunications
Author: Ganapati PandaPublisher: Springer
ISBN: 9811319065
Category : Technology & Engineering
Languages : en
Pages : 802
Book Description
The book discusses the latest developments and outlines future trends in the fields of microelectronics, electromagnetics and telecommunication. It contains original research works presented at the International Conference on Microelectronics, Electromagnetics and Telecommunication (ICMEET 2018), organised by GVP College of Engineering (A), Andhra Pradesh, India. The respective papers were written by scientists, research scholars and practitioners from leading universities, engineering colleges and R&D institutes from all over the world, and share the latest breakthroughs in and promising solutions to the most important issues facing today’s society.
Design and Analysis of CMOS Voltage Controlled Oscillator
Author: Gaurav MitalCMOS PLL Synthesizers: Analysis and Design
Author: Keliu ShuPublisher: Springer Science & Business Media
ISBN: 0387236694
Category : Technology & Engineering
Languages : en
Pages : 227
Book Description
Thanks to the advance of semiconductor and communication technology, the wireless communication market has been booming in the last two decades. It evolved from simple pagers to emerging third-generation (3G) cellular phones. In the meanwhile, broadband communication market has also gained a rapid growth. As the market always demands hi- performance and low-cost products, circuit designers are seeking hi- integration communication devices in cheap CMOS technology. The phase-locked loop frequency synthesizer is a critical component in communication devices. It works as a local oscillator for frequency translation and channel selection in wireless transceivers and broadband cable tuners. It also plays an important role as the clock synthesizer for data converters in the analog-and-digital signal interface. This book covers the design and analysis of PLL synthesizers. It includes both fundamentals and a review of the state-of-the-art techniques. The transient analysis of the third-order charge-pump PLL reveals its locking behavior accurately. The behavioral-level simulation of PLL further clarifies its stability limit. Design examples are given to clearly illustrate the design procedure of PLL synthesizers. A complete derivation of reference spurs in the charge-pump PLL is also presented in this book. The in-depth investigation of the digital CA modulator for fractional-N synthesizers provides insightful design guidelines for this important block.
Time-encoding VCO-ADCs for Integrated Systems-on-Chip
Author: Georges GielenPublisher: Springer Nature
ISBN: 3030880672
Category : Technology & Engineering
Languages : en
Pages : 118
Book Description
This book demonstrates why highly-digital CMOS time-encoding analog-to-digital converters incorporating voltage-controlled oscillators (VCOs) and time-to-digital converters (TDCs) are a good alternative to traditional switched-capacitor S-D modulators for power-efficient sensor, biomedical and communications applications. The authors describe the theoretical foundations and design methodology of such time-based ADCs from the basics to the latest developments. While most analog designers might notice some resemblance to PLL design, the book clearly highlights the differences to standard PLL circuit design and illustrates the design methodology with practical circuit design examples. Describes in detail the design methodology for CMOS time-encoding analog-to-digital converters that can be integrated along with digital logic in a nanometer System on Chip; Assists analog designers with the necessary change in design paradigm, highlighting differences between designing time-based ADCs and traditional analog circuits like switched-capacitor converters and PLLs; Uses a highly-visual, tutorial approach to the topic, including many practical examples of techniques introduced.
Analog CMOS Voltage Controlled Oscillator (VCO) in Phase Locked Loop (PLL)
Author: Vern Shyn KhawPublisher:
ISBN:
Category : Phase-locked loops
Languages : en
Pages : 89
Book Description
Author: Bin Wan