Design and Phase-noise Modeling of Temperature-compensated High Frequency MEMS-CMOS Reference Oscillators - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Design and Phase-noise Modeling of Temperature-compensated High Frequency MEMS-CMOS Reference Oscillators write by Seyed Hossein Miri Lavasani. This book was released on 2010. Design and Phase-noise Modeling of Temperature-compensated High Frequency MEMS-CMOS Reference Oscillators available in PDF, EPUB and Kindle. Frequency reference oscillator is a critical component of modern radio transceivers. Currently, most reference oscillators are based on low-frequency quartz crystals that are inherently bulky and incompatible with standard micro-fabrication processes. Moreover, their frequency limitation (200MHz) requires large up-conversion ratio in multigigahertz frequency synthesizers, which in turn, degrades the phase-noise. Recent advances in MEMS technology have made realization of high-frequency on-chip low phase-noise MEMS oscillators possible. Although significant research has been directed toward replacing quartz crystal oscillators with integrated micromechanical oscillators, their phase-noise performance is not well modeled. In addition, little attention has been paid to developing electronic frequency tuning techniques to compensate for temperature/process variation and improve the absolute frequency accuracy. The objective of this dissertation was to realize high-frequency temperature-compensated high-frequency (100MHz) micromechanical oscillators and study their phase-noise performance. To this end, low-power low-noise CMOS transimpedance amplifiers (TIA) that employ novel gain and bandwidth enhancement techniques are interfaced with high frequency (>100MHz) micromechanical resonators. The oscillation frequency is varied by a tuning network that uses frequency tuning enhancement techniques to increase the tuning range with minimal effect on the phase-noise performance. Taking advantage of extended frequency tuning range, and on-chip temperature-compensation circuitry is embedded with the sustaining circuitry to electronically temperature-compensate the oscillator. Finally, detailed study of the phase-noise in micromechanical oscillators is performed and analytical phase-noise models are derived.
Reference Clock Design for Low Power and Low Phase Noise with Temperature Compensation
Reference Clock Design for Low Power and Low Phase Noise with Temperature Compensation - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Reference Clock Design for Low Power and Low Phase Noise with Temperature Compensation write by Jabeom Koo. This book was released on 2016. Reference Clock Design for Low Power and Low Phase Noise with Temperature Compensation available in PDF, EPUB and Kindle. Low power and low phase noise RF frequency references are essential for applications such as high performance ADCs, high speed serial data links, and low power radios. They constitute a multi-billion dollar market in today’s electronic industry. Quartz crystal is the most commonly used mineral for generating a reference clock. However, it needs a complicated manufacturing process, which increases cost, and it cannot be integrated with CMOS circuits. This is reason why wafer scale high-Q MEMS resonators are becoming attractive alternatives to quartz owing to their small size, low cost and integration potential. However, oscillators using MEMS resonator perform poorly compared to quartz based oscillators in terms of close-in phase noise. Close-in phase noise is an important performance metric for a reference oscillator as it dominates the in-band phase noise of a frequency synthesizer in a radio. In addition, highly miniaturized MEMS resonator based oscillators have exhibited poor frequency stability over temperature. This characteristic is an issue, which limits the choice of the oscillator type in wireless application such as Bluetooth, Wi-Fi and GPS. The first part of this thesis addresses the close-in phase noise issue and proposes circuits with MEMS resonator such as AlN contour mode resonator and FBAR (thin-Film Bulk-Acoustic Resonator) to demonstrate solutions for improving the phase noise and lowering the power consumption. The proposed oscillator with FBAR culminates in achieving more than 10dB lower phase noise than that of conventional oscillator with 350uW power consumption. The following part of this thesis addresses the frequency drift of the reference clock when the temperature changes. The wireless application requires stringent and challenging spec. for the oscillator to generate a stable clock signal. For example, GPS needs to have less than 2ppm frequency drift over temperature. The first prototype of fully integrated oven-controlled temperature compensation system is thus introduced. This effort aims to have a ±1.6ppm stability reference clock with 150uK temperature resolution.
Temperature Compensated CMOS and MEMS-CMOS Oscillators for Clock Generators and Frequency References
Temperature Compensated CMOS and MEMS-CMOS Oscillators for Clock Generators and Frequency References - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Temperature Compensated CMOS and MEMS-CMOS Oscillators for Clock Generators and Frequency References write by Krishnakumar Sundaresan. This book was released on 2006. Temperature Compensated CMOS and MEMS-CMOS Oscillators for Clock Generators and Frequency References available in PDF, EPUB and Kindle. The purpose of this dissertation is to explore alternatives to quartz crystal based solutions to system clocking. While quartz has inherent advantages in terms of stability and cost, the inability to manufacture quartz in a standard silicon process impedes goals of miniaturization and system integration. A closer look at clocking requirements reveals widely different specifications for various applications. In addition to traditional CMOS oscillators such as ring and LC oscillators, the recent advent of micromachining technologies and MEMS resonators has provided a miniaturized, silicon alternative to quartz with potentially comparable performance levels. This provides the system designer with an option to make a clocking solution that most suits the system needs.
Design of High-Performance CMOS Voltage-Controlled Oscillators
Design of High-Performance CMOS Voltage-Controlled Oscillators - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Design of High-Performance CMOS Voltage-Controlled Oscillators write by Liang Dai. This book was released on 2003. Design of High-Performance CMOS Voltage-Controlled Oscillators available in PDF, EPUB and Kindle. 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.
The Design of Low Noise Oscillators
The Design of Low Noise Oscillators - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook The Design of Low Noise Oscillators write by Ali Hajimiri. This book was released on 2007-05-08. The Design of Low Noise Oscillators available in PDF, EPUB and Kindle. It is hardly a revelation to note that wireless and mobile communications have grown tremendously during the last few years. This growth has placed stringent requi- ments on channel spacing and, by implication, on the phase noise of oscillators. C- pounding the challenge has been a recent drive toward implementations of transceivers in CMOS, whose inferior 1/f noise performance has usually been thought to disqualify it from use in all but the lowest-performance oscillators. Low noise oscillators are also highly desired in the digital world, of course. The c- tinued drive toward higher clock frequencies translates into a demand for ev- decreasing jitter. Clearly, there is a need for a deep understanding of the fundamental mechanisms g- erning the process by which device, substrate, and supply noise turn into jitter and phase noise. Existing models generally offer only qualitative insights, however, and it has not always been clear why they are not quantitatively correct.
