Voltage references are fundamental to mixed signal converters which are widely used in elec- tronics. Hence there are signicant advantages in having the voltage reference operate with less power while minimizing area consumption and maintaining performance. Past designs have suered from issues related to process variations which adversely aect the temperature coe- cient of the circuit output. To compensate for these process variations, a means to modify the temperature coecient are proposed and experimentally veried with two circuit architectures. Five test chip samples implement these architectures in a 0.35 m CMOS process. Design methodologies for both architectures are presented. Design techniques include the use of a high-swing cascode to improve Line Sensitivity while minimizing additional power consumption, accounting for a well-matched layout, and the eect of leakage currents on the performance of the circuit. Layout schematics, performance gures, test methodologies and results are presented. Each circuit dissipates less than 4 nW and operates down to 0.9 V or better with Line Sensitivity and Power Supply Rejection Ratio of less than 0.15 %/V and -58 dB respectively, while consuming an area of 0.053 mm2 or less. The experimental average and median temperature coecient was less than 26 ppm/C and 22 ppm/C respectively in the #x0;20 C to 80 C range, with the best performance being less than 8.1 ppm/C. Areas of improvement and potential areas of future research are then identied to facilitate advancement of this work.

A practical overview of CMOS circuit design, this book covers the technology, analysis, and design techniques of voltage reference circuits. The design requirements covered follow modern CMOS processes, with an emphasis on low power, low voltage, and low temperature coefficient voltage reference design. Dedicating a chapter to each stage of the design process, the authors have organized the content to give readers the tools they need to implement the technologies themselves. Readers will gain an understanding of device characteristics, the practical considerations behind circuit topology, and potential problems with each type of circuit. Many design examples are used throughout, most of which have been tested with silicon implementation or employed in real-world products. This ensures that the material presented relevant to both students studying the topic as well as readers requiring a practical viewpoint. Covers CMOS voltage reference circuit design, from the basics through to advanced topics Provides an overview of basic device physics and different building blocks of voltage reference designs Features real-world examples based on actual silicon implementation Includes analytical exercises, simulation exercises, and silicon layout exercises, giving readers guidance and design layout experience for voltage reference circuits Solution manual available to instructors from the book’s companion website This book is highly useful for graduate students in VLSI design, as well as practicing analog engineers and IC design professionals. Advanced undergraduates preparing for further study in VLSI will also find this book a helpful companion text.

A traditional bandgap reference voltage has a value approximately equal to 1.2V. This is an inconvenient value to obtain in short-channel CMOS circuits where the nominal power supply voltage is 1.2V or lower. Here, a simple circuit is presented to generate a reference voltage between 600mV and 800mV, based on the threshold voltage of a MOS device, which will be suitable for biasing transistors in strong inversion as well as for use in 6-bit data converters needed for high speed data communication systems. The circuit uses a novel, but simple, method for generating the temperature coefficients needed for generating a stable voltage reference across temperature. The core circuit produces a PTAT current that when passed through a diode-connected device, with a CTAT threshold voltage, will produce a voltage that is stable across temperature. The measured results demonstrate an average voltage variation of 4.62mV across five chips, each containing eight voltage reference circuits, and a minimum voltage variation of 1.1mV from 0°C to 80°C. A variation of the proposed circuit replaces the BJTs with MOSFETs to achieve smaller area, and simulation results indicate even less voltage variation across temperature.

This book is a detailed compendium of these major advancements focusing exclusively on the emerging broadband wireless communication technologies which support broadband wireless data rate transmissions.

This book describes an alternative method of realizing accurate on-chip frequency references in standard CMOS processes. This method exploits the thermal-diffusivity of silicon, i.e. the rate at which heat diffuses through a silicon substrate. This is the first book describing the design of such electrothermal frequency references. It includes the necessary theory, supported by practical realizations that achieve inaccuracies as low as 0.1% and thus demonstrate the feasibility of this approach. The book also includes several circuit and system-level solutions to the precision circuit design challenges encountered during the design of such frequency references.

Current Sources and Voltage References provides fixed, well-regulated levels of current or voltage within a circuit. These are two of the most important “building blocks “ of analog circuits, and are typically used in creating most analog IC designs. Part 1 shows the reader how current sources are created, how they can be optimized, and how they can be utilized by the OEM circuit designer. The book serves as a “must-have reference for the successful development of precision circuit applications. It shows practical examples using either BJTs, FETs, precision op amps, or even matched CMOS arrays being used to create highly accurate current source designs, ranging from nanoAmps to Amps. In each chapter the most important characteristics of the particular semiconductor type being studied are carefully reviewed. This not only serves as a helpful refresher for experienced engineers, but also as a good foundation for all EE student coursework, and includes device models and relevant equations. Part 2 focuses on semiconductor voltage references, from their design to their various practical enhancements. It ranges from the simple Zener diode to today’s most advanced topologies, including Analog Devices’ XFET® and Intersil’s FGATM (invented while this book was being written). Over 300 applications and circuit diagrams are shown throughout this easy-to-read, practical reference book. * Discusses how to design low-noise, precision current sources using matched transistor pairs. * Explains the design of high power current sources with power MOSFETs * Gives proven techniques to reduce drift and improve accuracy in voltage references.