Willy M.C. Sansen – författare

In the first part the AMGIE analog synthesis system is described. AMGIE is the first analog synthesis system that automates the full design process from specifications down to verified layout. It is targeted to the design of moderate-complexity circuits. It relies on design and circuit knowledge stored in the tool's libraries and can be used by both novice and experienced analog designers as well as system-level designers. The inner workings are explained in detail, with (practical) examples to demonstrate how the implemented algorithms and techniques work. Experimental results obtained with the AMGIE system are reported, including actual fabricated and measured circuits. The second approach, i.e. the systematic design of high-performance analog circuits, is discussed in the second part of the book. This approach is supported by tools to boost the productivity of the designer. An example of such a tool is Mondriaan, that is targeted towards the automatic layout generation of highly regular analog blocks. The proposed systematic design methodology is then applied to the design of high-accuracy current-steering digital to analog converters (DACs). The full design path is discussed in detail. Both complementary approaches increase analog design productivity. Design times of the different design experiments undertaken are reported throughout the book to demonstrate this.

This book contains the extended and revised editions of all the talks of the ninth AACD Workshop held in Hotel Bachmair, April 11 - 13 2000 in Rottach-Egem, Germany. The local organization was managed by Rudolf Koch of Infineon Technologies AG, Munich, Germany. The program consisted of six tutorials per day during three days. Experts in the field presented these tutorials and state of the art information is communicated. The audience at the end of the workshop selects program topics for the following workshop. The program committee, consisting of Johan Huijsing of Delft University of Technology, Willy Sansen of Katholieke Universiteit Leuven and Rudy van de Plassche of Broadcom Netherlands BV Bunnik elaborates the selected topics into a three-day program and selects experts in the field for presentation. Each AACD Workshop has given rise to publication of a book by Kluwer entitled "Analog Circuit Design". A series of nine books in a row provides valuable information and good overviewsof all analog circuit techniques concerning design, CAD, simulation and device modeling. These books can be seen as a reference to those people involved in analog and mixed signal design. The aim of the workshop is to brainstorm on new and valuable design ideas in the area of analog circuit design. It is the hope of the program committee that this ninth book continues the tradition of emerging contributions to the design of analog and mixed signal systems in Europe and the rest of the world.

The analysis and prediction of nonlinear behavior in electronic circuits has long been a topic of concern for analog circuit designers. The recent explosion of interest in portable electronics such as cellular telephones, cordless telephones and other applications has served to reinforce the importance of these issues. The need now often arises to predict and optimize the distortion performance of diverse electronic circuit configurations operating in the gigahertz frequency range, where nonlinear reactive effects often dominate. However, there have historically been few sources available from which design engineers could obtain information on analysis tech­ niques suitable for tackling these important problems. I am sure that the analog circuit design community will thus welcome this work by Dr. Wambacq and Professor Sansen as a major contribution to the analog circuit design literature in the area of distortion analysis of electronic circuits. I am personally looking forward to hav­ing a copy readily available for reference when designing integrated circuits for communication systems.

This book contains the revised contributions of 18 tutorial speakers at the seventh AACD '98 in Copenhagen, April 28-30, 1998. The conference was organized by OIe Olesen, ofthe Technical University of Denmark. The pro gram committee consisted of Johan H. Huijsing from Delft University ofTechnology, The Netherlands, Willy Samsen from the Katholieke Universiteit Leuven, Belgium and Rudy J. van de Plassche, Philips Research, The Netherlands. The pro gram was concentrated around three important topics in analog circuit design. Each of these three topics has been covered by six papers. Each of the three chapters of this book contains the six papers of one topic. The three topics are: I-Volt Electronics Design and implementation ofMixed Modes Systems. Low-Noise and RF power Amplifies for the communication. Other topics, which have been covered in this series before are: 1992 OpAmps ADC's AnalogCAD. 1993 Mixed-Mode AlD design Sensor Interfaces Communication circuits. 1994 Low-Power low-Voltage Integrated Filters Smart Power. 1995 Low-Noise, Low-Power, Low-Voltage Mixed Mode with CAD Tirals Voltage, Current and Time References. vii viii 1996 RF CMOS circuit design BandpassSigma Delta and other Converters Translinear circuits.1997 RF A-D Converters Sensor and Actuator Interfaces Low-noise Oscillators, PLL's and and Synthesizers. We hope to serve the analog design community with these series of books and plan to continue this series in the future.

Design of Low-Voltage Low-Power CMOS Delta-Sigma A/D Converters investigates the feasibility of designing Delta-Sigma Analog to Digital Converters for very low supply voltage (lower than 1.5V) and low power operation in standard CMOS processes. The chosen technique of implementation is the Switched Opamp Technique which provides Switched Capacitor operation at low supply voltage without the need to apply voltage multipliers or low VtMOST devices. A method of implementing the classic single loop and cascaded Delta-Sigma modulator topologies with half delay integrators is presented. Those topologies are studied in order to find the parameters that maximise the performance in terms of peak SNR. Based on a linear model, the performance degradations of higher order single loop and cascaded modulators, compared to a hypothetical ideal modulator, are quantified. An overview of low voltage Switched Capacitor design techniques, such as the use of voltage multipliers, low VtMOST devices and the Switched Opamp Technique, is given. An in-depth discussion of the present status of the Switched Opamp Technique covers the single-ended Original Switched Opamp Technique, the Modified Switched Opamp Technique, which allows lower supply voltage operation, and differential implementation including common mode control techniques. The restrictions imposed on the analog circuits by low supply voltage operation are investigated. Several low voltage circuit building blocks, some of which are new, are discussed. A new low voltage class AB OTA, especially suited for differential Switched Opamp applications, together with a common mode feedback amplifier and a comparator are presented and analyzed. As part of a systematic top-down design approach, the non-ideal charge transfer of the Switched Opamp integrator cell is modeled, based upon several models of the main opamp non-ideal characteristics. Behavioral simulations carried out with these models yield the required opamp specifications that ensure that the intended performance is met in an implementation. A power consumption analysis is performed. The influence of all design parameters, especially the low power supply voltage, is highlighted. Design guidelines towards low power operation are distilled. Two implementations are presented together with measurement results. The first one is a single-ended implementation of a Delta-Sigma ADC operating with 1.5V supply voltage and consuming 100 &mgr;W for a 74 dB dynamic range in a 3.4 kHz bandwidth. The second implementation is differential and operates with 900 mV. It achieves 77 dB dynamic range in 16 kHz bandwidth and consumes 40 &mgr;W. Design of Low-Voltage Low-Power CMOS Delta-Sigma A/D Converters is essential reading for analog design engineers and researchers.

Analog integrated circuits are very important as interfaces between the digital parts of integrated electronic systems and the outside world. A large portion of the effort involved in designing these circuits is spent in the layout phase. Whereas the physical design of digital circuits is automated to a large extent, the layout of analog circuits is still a manual, time-consuming and error-prone task. This is mainly due to the continuous nature of analog signals, which causes analog circuit performance to be very sensitive to layout parasitics. The parasitic elements associated with interconnect wires cause loading and coupling effects that degrade the frequency behaviour and the noise performance of analog circuits. Device mismatch and thermal effects put a fundamental limit on the achievable accuracy of circuits. For successful automation of analog layout, advanced place and route tools that can handle these critical parasitics are required. In the past, automatic analog layout tools tried to optimize the layout without quantifying the performance degradation introduced by layout parasitics. Therefore, it was not guaranteed that the resulting layout met the specifications and one or more layout iterations could be needed. In Analog Layout Generation for Performance and Manufacturability, the authors propose a performance driven layout strategy to overcome this problem. In this methodology, the layout tools are driven by performance constraints, such that the final layout, with parasitic effects, still satisfies the specifications of the circuit. The performance degradation associated with an intermediate layout solution is evaluated at runtime using predetermined sensitivities. In contrast with other performance driven layout methodologies, the tools proposed in this book operate directly on the performance constraints, without an intermediate parasitic constraint generation step. This approach makes a completeand sensible trade-off between the different layout alternatives possible at runtime and therefore eliminates the possible feedback route between constraint derivation, placement and layout extraction. Besides its influence on the performance, layout also has a profound impact on the yield and testability of an analog circuit. In Analog Layout Generation for Performance and Manufacturability, the authors outline a new criterion to quantify the detectability of a fault and combine this with a yield model to evaluate the testability of an integrated circuit layout. They then integrate this technique with their performance driven routing algorithm to produce layouts that have optimal manufacturability while still meeting their performance specifications. Analog Layout Generation for Performance and Manufacturability will be of interest to analog engineers, researchers and students.

This new book on Analog Circuit Design contains the revised contributions of all the tutorial speakers of the eight workshop AACD (Advances in Analog Circuit Design), which was held at Nice, France on March 23-25, 1999. The workshop was organized by Yves Leduc of TI Nice, France. The program committee consisted of Willy Sansen, K.U.Leuven, Belgium, Han Huijsing, T.U.Delft, The Netherlands and Rudy van de Plassche, T.U.Eindhoven, The Netherlands. The aim of these AACD workshops is to bring together a restricted group of about 100 people who are personally advancing the frontiers of analog circuit design to brainstorm on new possibilities and future developments in a restricted number of fields. They are concentrated around three topics. In each topic six speakers give a tutorial presentation. Eighteen papers are thus included in this book. The topics of 1999 are: (X)DSL and other communication systems RF MOST models Integrated filters and oscillators The other topics, which have been coverd before, are: 1992 Operational amplifiers A-D Converters Analog CAD 1993 Mixed-mode A+D design Sensor interfaces Communication circuits 1994 Low-power low-voltage design Integrated filters Smart power 1995 Low-noise low-power low-voltge design Mixed-mode design with CAD tools Voltage, current and time references vii viii 1996 RF CMOS circuit design Bandpass sigma-delta and other data converters Translinear circuits 1997 RF A-D Converters Sensor and actuator interfaces Low-noise oscillators, PLL's and synthesizers 1998 I-Volt electronics Design and implementation of mixed-mode systems Low-noise amplifiers and RF power amplifiers for telecommunications

Analog circuit design has grown in importance because so many circuits cannot be realized with digital techniques. Examples are receiver front-ends, particle detector circuits, etc. Actually, all circuits which require high precision, high speed and low power consumption need analog solutions. High precision also needs low noise. Much has been written already on low noise design and optimization for low noise. Very little is available however if the source is not resistive but capacitive or inductive as is the case with antennas or semiconductor detectors. This book provides design techniques for these types of optimization. This book is thus intended firstly for engineers on senior or graduate level who have already designed their first operational amplifiers and want to go further. It is especially for engineers who do not want just a circuit but the best circuit. Design techniques are given that lead to the best performance within a certain technology. Moreover, this is done for all important technologies such as bipolar, CMOS and BiCMOS. Secondly, this book is intended for engineers who want to understand what they are doing. The design techniques are intended to provide insight. In this way, the design techniques can easily be extended to other circuits as well. Also, the design techniques form a first step towards design automation. Thirdly, this book is intended for analog design engineers who want to become familiar with both bipolar and CMOS technologies and who want to learn more about which transistor to choose in BiCMOS.

It is a great honor to provide a few words of introduction for Dr. Georges Gielen's and Prof. Willy Sansen's book "Symbolic analysis for automated design of analog integrated circuits". The symbolic analysis method presented in this book represents a significant step forward in the area of analog circuit design. As demonstrated in this book, symbolic analysis opens up new possibilities for the development of computer-aided design (CAD) tools that can analyze an analog circuit topology and automatically size the components for a given set of specifications. Symbolic analysis even has the potential to improve the training of young analog circuit designers and to guide more experienced designers through second-order phenomena such as distortion. This book can also serve as an excellent reference for researchers in the analog circuit design area and creators of CAD tools, as it provides a comprehensive overview and comparison of various approaches for analog circuit design automation and an extensive bibliography. The world is essentially analog in nature, hence most electronic systems involve both analog and digital circuitry. As the number of transistors that can be integrated on a single integrated circuit (IC) substrate steadily increases over time, an ever increasing number of systems will be implemented with one, or a few, very complex ICs because of their lower production costs.

Many interesting design trends are shown by the six papers on operational amplifiers (Op Amps). Firstly. there is the line of stand-alone Op Amps using a bipolar IC technology which combines high-frequency and high voltage. This line is represented in papers by Bill Gross and Derek Bowers. Bill Gross shows an improved high-frequency compensation technique of a high quality three stage Op Amp. Derek Bowers improves the gain and frequency behaviour of the stages of a two-stage Op Amp. Both papers also present trends in current-mode feedback Op Amps. Low-voltage bipolar Op Amp design is presented by leroen Fonderie. He shows how multipath nested Miller compensation can be applied to turn rail-to-rail input and output stages into high quality low-voltage Op Amps. Two papers on CMOS Op Amps by Michael Steyaert and Klaas Bult show how high speed and high gain VLSI building blocks can be realised. Without departing from a single-stage OT A structure with a folded cascode output, a thorough high frequency design technique and a gain-boosting technique contributed to the high-speed and the high-gain achieved with these Op Amps. . Finally. Rinaldo Castello shows us how to provide output power with CMOS buffer amplifiers. The combination of class A and AB stages in a multipath nested Miller structure provides the required linearity and bandwidth.

Devoted to the design of CMOS continuous-time filters, this book shows that CMOS is employed because the most complex integrated circuits have been realized with this technology for two decades. The most important advantages and drawbacks of continuous-time filters are clearly shown. The transfer function is one of the most important filter parameters but several others (like intermodulation distortion; power-supply rejection ratio; noise level and dynamic range) are fundamental in the design of high-performance systems. Special attention is paid to the practical aspects of the design, which shows the difference between an academic design and an industrial design. Step-by-step design procedures are often used to clarify the use of the techniques and topologies. The organisation of this text is hierarchical, starting with the design consideration of the basic building blocks and ending with the design of several high-performance continuous-time filters. Most of the circuits have been fabricated, theoretically analyzed and simulated, and silicon measurement results are compared with each other.This book can be used as a text book for senior or graduate courses in this field and can also be useful for industrial engineers.

The ever-increasing complexity and speed of digital circuits has considerably modified the architecture of integrated signal processing systems, resulting in the analogue parts of the system being pushed towards the boundaries of the signal processing chain. The specification requirements of these analogue interface circuits are becoming very strict, in order to fully benefit from the speed performance and the high dynamic range offered by digital circuits. This book analyzes the analogue interfaces of a digital signal processing chain, and presents techniques to obtain maximum performance for various technologies and applications. The book serves as a general introduction and as a reference work in the fields of low-distortion analogue circuits and over-sampled data converters. It can also be used as the text for advanced courses covering these topics.

Some examples have been presented of BiCMOS circuit design in mixed- signal ASICs. It is by no means an exhaustive list. Many cells have not been mentioned, including 300MHz CMOS Video DACs, 20 Bit Sigma-Delta ADCs, Real-time and Switched-Cap Filters, Line Drivers and Receivers and many more. References. [1] J.Corcoran "High Speed Sample and Hold and Analog-to-Digital Converter Circuits",Advances in Analog Circuit Design, April1992. [2] Y.S.Yee,L.M.Terman and L.G.Heller "A lmV MOS comparator," IEEE J. of Solid-State Circuits, vol. SC-13, June 1978. [3] M.Timko and P.Holloway "Circuit Techniques for Achieving High Speed- High Resolution AID Conversion" IEEE Journal of Solid-State Circuits, vol. SC-15, No.6, December 1980. [4] W.H. Gross "New High Speed Amplifier Design, Design Techniques and Layout Problems", Advances in Analog Circuit Design, April 1992. MIXED SIGNAL ASIC DESIGN FOR AUTOMOTIVE AND INDUSTRIAL APPLICATIONS H. Casicr Mietcc Alcatel, Brussels, Belgium ABSTRACT This paper describes the special aspects of mixed signal design in the ASIC environment.The knowledge of the application specific environment and of the function of the ASIC can be used advantageously to lower the cost and to enhance the performance at all levels of design. Several examples of this cost improvement and performance enhancement at device, circuit and system level are shown.

The realization of signal sampling and quantization at high sample rates with low power dissipation is an important goal in many applications, includ­ ing portable video devices such as camcorders, personal communication devices such as wireless LAN transceivers, in the read channels of magnetic storage devices using digital data detection, and many others. This paper describes architecture and circuit approaches for the design of high-speed, low-power pipeline analog-to-digital converters in CMOS. Here the term high speed is taken to imply sampling rates above 1 Mhz. In the first section the dif­ ferent conversion techniques applicable in this range of sample rates is dis­ cussed. Following that the particular problems associated with power minimization in video-rate pipeline ADCs is discussed. These include optimi­ zation of capacitor sizes, design of low-voltage transmission gates, and opti­ mization of switched capacitor gain blocks and operational amplifiers for minimum power dissipation. As an example of the application of these tech­ niques, the design of a power-optimized lO-bit pipeline AID converter (ADC) that achieves =1. 67 mW per MS/s of sampling rate from 1 MS/s to 20 MS/s is described. 2. Techniques for CMOS Video-Rate AID Conversion Analog-to-digital conversion techniques can be categorized in many ways. One convenient means of comparing techniques is to examine the number of "analog clock cycles" required to produce one effective output sample of the signal being quantized.

This volume of "Analog Circuit Design" concentrates on three topics: low-noise, low-power, low-voltage; mixed-mode design with CAD tools; and voltage, current and time references. The book contains six papers on each topic, written by internationally recognized experts. The papers are tutorial in nature and aim to make a contribution to improving the design of analogue circuits. The book is divided into three parts. Part 1, "Low-Noise, Low-Power, Low-Voltage", concentrates on the problems of the matching properties of high frequency MOS circuits caused by the continuous reduction in the size of integrated devices. These problems are considered in the light of maintaining the benefits of greater bandwidth and lower power consumption. Part 2, "Mixed Mode Design with CAD Tools", looks at the practicalities of providing CAD tools for circuits containing both digital and analogue elements. The papers consider both the simulation and synthesis aspects of designing CAD tools suitable for such designs. Part 3, "Voltage, Current and Time References", contains much new material describing all aspects of these reference circuits.This book is intended as a reference source for analogue design engineers and researchers wishing to keep abreast with the latest developments in the field. The tutorial nature of the contributions also makes it suitable for use in an advanced course.

This book contains the revised contributions of all the speakers of the fifth AACD Workshop which was held in Lausanne on April 2-4, 1996. It was organized by Dr Vlado Valence of the EPFL University and MEAD of Lausanne. The program consisted of six tutorials per day during three days. The tutorials were presented by experts in the field. They were selected by a program committee consisting of Prof. Willy Sansen of the Katholieke Universiteit Leuven, Prof. Rudy van de Plassche of Philips Research and the University of Technology Eindhoven and Prof. 10han Huijsing of the Delft University of Technology. The three topics mentioned above have been selected because of their importance in present days analog design. The other topics that have been discussed before are: in 1992 : Operational amplifiers Analog to digital convereters Analog computer aided design in 1993 : Mixed AID cicuit design Sensor interface circuits Communication circuits in 1994 : Low-power low-voltage design Integrated filters Smart power circuits in 1995 : Low-noise, low-power, low-voltage design Mixed-mode design with CAD tools Voltage, current and time references Each AACD workhop has given rise to the publication of a book by Kluwer entitled "Analog Circuit Design". This is thus the fifth book. This series of books provides a valuable overview of all analog circuit design techniques and achievements. It is a reference for whoever is engaged in this discipline.

This book contains the extended and revised versions of the talks of all speakers presented at the sixth AACD Workshop held in Villa Olmo, April 2-4 1997 Como, Italy. The local chairman was Pietro Erratico and the organization was performed by Isabella De Quattro both of SGS- Thomson Microelectronics Cornareda and Agrate Brianza Italy. The program consisted of six tutorials per day during three days. These tutorials were presented by experts in the field to give state of the art information. Program topics for the following workshop are selected by the audience at the end of the workshop. The program committee, consisting of 10han Huijsing of Delft University of Technology, Willy Sansen of Katholieke Universiteit Leuven and Rudy van de Plassche of Philips Research Labs and University of Technology Eindhoven elaborates the selected topics into a three day program and selects the experts in the field for presentation. Each AACD Workshop has given rise to the publication of a book by Kluwer entitled "Analog Circuit Design".This series of six books in a row provides a valuable overview of all analog circuit techniques concerning design, CAD, simulation and device modeling and can be seen as a reference to those involved in analog circuits.

Static and Dynamic Performance Limitations for High Speed D/A Converters discusses the design and implementation of high speed current-steering CMOS digital-to-analog converters. Starting from the definition of the basic specifications for a D/A converter, the elements determining the static and dynamic performance are identified. Different guidelines based on scientific derivations are suggested to optimize this performance. Furthermore, a new closed formula has been derived to account for the influence of the transistor mismatch on the achievable resolution of the current-steering D/A converter. To allow a thorough understanding of the dynamic behavior, a new factor has been introduced. Moreover, the frequency dependency of the output impedance introduces harmonic distortion components which can limit the maximum attainable spurious free dynamic range. The validity of all the derived concepts has been demonstrated in the design and implementation of different D/A converters ranging from high resolution to high speed devices, which also resulted in the first published 10 bit 1GSample/s CMOS current-steering D/A converter.Finally, the last part of the book gives an overview on different existing transistor mismatch models and the link with the static performance of the D/A converter. Static and Dynamic Performance Limitations for High Speed D/A Converters serves as an invaluable reference book and may be used as a text for advanced courses on the subject.

This book contains the extended and revised editions of all the talks of the ninth AACD Workshop held in Hotel Bachmair, April 11 - 13 2000 in Rottach-Egem, Germany. The local organization was managed by Rudolf Koch of Infineon Technologies AG, Munich, Germany. The program consisted of six tutorials per day during three days. Experts in the field presented these tutorials and state of the art information is communicated. The audience at the end of the workshop selects program topics for the following workshop. The program committee, consisting of Johan Huijsing of Delft University of Technology, Willy Sansen of Katholieke Universiteit Leuven and Rudy van de Plassche of Broadcom Netherlands BV Bunnik elaborates the selected topics into a three-day program and selects experts in the field for presentation. Each AACD Workshop has given rise to publication of a book by Kluwer entitled "Analog Circuit Design". A series of nine books in a row provides valuable information and good overviewsof all analog circuit techniques concerning design, CAD, simulation and device modeling. These books can be seen as a reference to those people involved in analog and mixed signal design. The aim of the workshop is to brainstorm on new and valuable design ideas in the area of analog circuit design. It is the hope of the program committee that this ninth book continues the tradition of emerging contributions to the design of analog and mixed signal systems in Europe and the rest of the world.

The analysis and prediction of nonlinear behavior in electronic circuits has long been a topic of concern for analog circuit designers. The recent explosion of interest in portable electronics such as cellular telephones, cordless telephones and other applications has served to reinforce the importance of these issues. The need now often arises to predict and optimize the distortion performance of diverse electronic circuit configurations operating in the gigahertz frequency range, where nonlinear reactive effects often dominate. However, there have historically been few sources available from which design engineers could obtain information on analysis tech­ niques suitable for tackling these important problems. I am sure that the analog circuit design community will thus welcome this work by Dr. Wambacq and Professor Sansen as a major contribution to the analog circuit design literature in the area of distortion analysis of electronic circuits. I am personally looking forward to hav­ing a copy readily available for reference when designing integrated circuits for communication systems.

This book contains the revised contributions of 18 tutorial speakers at the seventh AACD '98 in Copenhagen, April 28-30, 1998. The conference was organized by OIe Olesen, ofthe Technical University of Denmark. The pro gram committee consisted of Johan H. Huijsing from Delft University ofTechnology, The Netherlands, Willy Samsen from the Katholieke Universiteit Leuven, Belgium and Rudy J. van de Plassche, Philips Research, The Netherlands. The pro gram was concentrated around three important topics in analog circuit design. Each of these three topics has been covered by six papers. Each of the three chapters of this book contains the six papers of one topic. The three topics are: I-Volt Electronics Design and implementation ofMixed Modes Systems. Low-Noise and RF power Amplifies for the communication. Other topics, which have been covered in this series before are: 1992 OpAmps ADC's AnalogCAD. 1993 Mixed-Mode AlD design Sensor Interfaces Communication circuits. 1994 Low-Power low-Voltage Integrated Filters Smart Power. 1995 Low-Noise, Low-Power, Low-Voltage Mixed Mode with CAD Tirals Voltage, Current and Time References. vii viii 1996 RF CMOS circuit design BandpassSigma Delta and other Converters Translinear circuits.1997 RF A-D Converters Sensor and Actuator Interfaces Low-noise Oscillators, PLL's and and Synthesizers. We hope to serve the analog design community with these series of books and plan to continue this series in the future.

Design of Low-Voltage Low-Power CMOS Delta-Sigma A/D Converters investigates the feasibility of designing Delta-Sigma Analog to Digital Converters for very low supply voltage (lower than 1.5V) and low power operation in standard CMOS processes. The chosen technique of implementation is the Switched Opamp Technique which provides Switched Capacitor operation at low supply voltage without the need to apply voltage multipliers or low VtMOST devices. A method of implementing the classic single loop and cascaded Delta-Sigma modulator topologies with half delay integrators is presented. Those topologies are studied in order to find the parameters that maximise the performance in terms of peak SNR. Based on a linear model, the performance degradations of higher order single loop and cascaded modulators, compared to a hypothetical ideal modulator, are quantified. An overview of low voltage Switched Capacitor design techniques, such as the use of voltage multipliers, low VtMOST devices and the Switched Opamp Technique, is given. An in-depth discussion of the present status of the Switched Opamp Technique covers the single-ended Original Switched Opamp Technique, the Modified Switched Opamp Technique, which allows lower supply voltage operation, and differential implementation including common mode control techniques. The restrictions imposed on the analog circuits by low supply voltage operation are investigated. Several low voltage circuit building blocks, some of which are new, are discussed. A new low voltage class AB OTA, especially suited for differential Switched Opamp applications, together with a common mode feedback amplifier and a comparator are presented and analyzed. As part of a systematic top-down design approach, the non-ideal charge transfer of the Switched Opamp integrator cell is modeled, based upon several models of the main opamp non-ideal characteristics. Behavioral simulations carried out with these models yield the required opamp specifications that ensure that the intended performance is met in an implementation. A power consumption analysis is performed. The influence of all design parameters, especially the low power supply voltage, is highlighted. Design guidelines towards low power operation are distilled. Two implementations are presented together with measurement results. The first one is a single-ended implementation of a Delta-Sigma ADC operating with 1.5V supply voltage and consuming 100 &mgr;W for a 74 dB dynamic range in a 3.4 kHz bandwidth. The second implementation is differential and operates with 900 mV. It achieves 77 dB dynamic range in 16 kHz bandwidth and consumes 40 &mgr;W. Design of Low-Voltage Low-Power CMOS Delta-Sigma A/D Converters is essential reading for analog design engineers and researchers.

Analog integrated circuits are very important as interfaces between the digital parts of integrated electronic systems and the outside world. A large portion of the effort involved in designing these circuits is spent in the layout phase. Whereas the physical design of digital circuits is automated to a large extent, the layout of analog circuits is still a manual, time-consuming and error-prone task. This is mainly due to the continuous nature of analog signals, which causes analog circuit performance to be very sensitive to layout parasitics. The parasitic elements associated with interconnect wires cause loading and coupling effects that degrade the frequency behaviour and the noise performance of analog circuits. Device mismatch and thermal effects put a fundamental limit on the achievable accuracy of circuits. For successful automation of analog layout, advanced place and route tools that can handle these critical parasitics are required. In the past, automatic analog layout tools tried to optimize the layout without quantifying the performance degradation introduced by layout parasitics. Therefore, it was not guaranteed that the resulting layout met the specifications and one or more layout iterations could be needed. In Analog Layout Generation for Performance and Manufacturability, the authors propose a performance driven layout strategy to overcome this problem. In this methodology, the layout tools are driven by performance constraints, such that the final layout, with parasitic effects, still satisfies the specifications of the circuit. The performance degradation associated with an intermediate layout solution is evaluated at runtime using predetermined sensitivities. In contrast with other performance driven layout methodologies, the tools proposed in this book operate directly on the performance constraints, without an intermediate parasitic constraint generation step. This approach makes a completeand sensible trade-off between the different layout alternatives possible at runtime and therefore eliminates the possible feedback route between constraint derivation, placement and layout extraction. Besides its influence on the performance, layout also has a profound impact on the yield and testability of an analog circuit. In Analog Layout Generation for Performance and Manufacturability, the authors outline a new criterion to quantify the detectability of a fault and combine this with a yield model to evaluate the testability of an integrated circuit layout. They then integrate this technique with their performance driven routing algorithm to produce layouts that have optimal manufacturability while still meeting their performance specifications. Analog Layout Generation for Performance and Manufacturability will be of interest to analog engineers, researchers and students.

This new book on Analog Circuit Design contains the revised contributions of all the tutorial speakers of the eight workshop AACD (Advances in Analog Circuit Design), which was held at Nice, France on March 23-25, 1999. The workshop was organized by Yves Leduc of TI Nice, France. The program committee consisted of Willy Sansen, K.U.Leuven, Belgium, Han Huijsing, T.U.Delft, The Netherlands and Rudy van de Plassche, T.U.Eindhoven, The Netherlands. The aim of these AACD workshops is to bring together a restricted group of about 100 people who are personally advancing the frontiers of analog circuit design to brainstorm on new possibilities and future developments in a restricted number of fields. They are concentrated around three topics. In each topic six speakers give a tutorial presentation. Eighteen papers are thus included in this book. The topics of 1999 are: (X)DSL and other communication systems RF MOST models Integrated filters and oscillators The other topics, which have been coverd before, are: 1992 Operational amplifiers A-D Converters Analog CAD 1993 Mixed-mode A+D design Sensor interfaces Communication circuits 1994 Low-power low-voltage design Integrated filters Smart power 1995 Low-noise low-power low-voltge design Mixed-mode design with CAD tools Voltage, current and time references vii viii 1996 RF CMOS circuit design Bandpass sigma-delta and other data converters Translinear circuits 1997 RF A-D Converters Sensor and actuator interfaces Low-noise oscillators, PLL's and synthesizers 1998 I-Volt electronics Design and implementation of mixed-mode systems Low-noise amplifiers and RF power amplifiers for telecommunications

Analog circuit design has grown in importance because so many circuits cannot be realized with digital techniques. Examples are receiver front-ends, particle detector circuits, etc. Actually, all circuits which require high precision, high speed and low power consumption need analog solutions. High precision also needs low noise. Much has been written already on low noise design and optimization for low noise. Very little is available however if the source is not resistive but capacitive or inductive as is the case with antennas or semiconductor detectors. This book provides design techniques for these types of optimization. This book is thus intended firstly for engineers on senior or graduate level who have already designed their first operational amplifiers and want to go further. It is especially for engineers who do not want just a circuit but the best circuit. Design techniques are given that lead to the best performance within a certain technology. Moreover, this is done for all important technologies such as bipolar, CMOS and BiCMOS. Secondly, this book is intended for engineers who want to understand what they are doing. The design techniques are intended to provide insight. In this way, the design techniques can easily be extended to other circuits as well. Also, the design techniques form a first step towards design automation. Thirdly, this book is intended for analog design engineers who want to become familiar with both bipolar and CMOS technologies and who want to learn more about which transistor to choose in BiCMOS.

Many interesting design trends are shown by the six papers on operational amplifiers (Op Amps). Firstly. there is the line of stand-alone Op Amps using a bipolar IC technology which combines high-frequency and high voltage. This line is represented in papers by Bill Gross and Derek Bowers. Bill Gross shows an improved high-frequency compensation technique of a high quality three stage Op Amp. Derek Bowers improves the gain and frequency behaviour of the stages of a two-stage Op Amp. Both papers also present trends in current-mode feedback Op Amps. Low-voltage bipolar Op Amp design is presented by leroen Fonderie. He shows how multipath nested Miller compensation can be applied to turn rail-to-rail input and output stages into high quality low-voltage Op Amps. Two papers on CMOS Op Amps by Michael Steyaert and Klaas Bult show how high speed and high gain VLSI building blocks can be realised. Without departing from a single-stage OT A structure with a folded cascode output, a thorough high frequency design technique and a gain-boosting technique contributed to the high-speed and the high-gain achieved with these Op Amps. . Finally. Rinaldo Castello shows us how to provide output power with CMOS buffer amplifiers. The combination of class A and AB stages in a multipath nested Miller structure provides the required linearity and bandwidth.

High-Performance CMOS Continuous-Time Filters is devoted to the design of CMOS continuous-time filters. CMOS is employed because the most complex integrated circuits have been realized with this technology for two decades. The most important advantages and drawbacks of continuous-time filters are clearly shown. The transfer function is one of the most important filter parameters but several others (like intermodulation distortion, power-supply rejection ratio, noise level and dynamic range) are fundamental in the design of high-performance systems. Special attention is paid to the practical aspects of the design, which shows the difference between an academic design and an industrial design. A clear understanding of the behavior of the circuits and techniques is preferred over complex equations or interpretation of simulated results. Step-by-step design procedures are very often used to clarify the use of the techniques and topologies.The organization of this text is hierarchical, starting with the design consideration of the basic building blocks and ending with the design of several high-performance continuous-time filters. Most of the circuits have been fabricated, theoretically analyzed and simulated, and silicon measurement results are compared with each other.High-Performance CMOS Continuous-Time Filters can be used as a text book for senior or graduate courses on this topic and can also be useful for industrial engineers as a reference book.

Some examples have been presented of BiCMOS circuit design in mixed- signal ASICs. It is by no means an exhaustive list. Many cells have not been mentioned, including 300MHz CMOS Video DACs, 20 Bit Sigma-Delta ADCs, Real-time and Switched-Cap Filters, Line Drivers and Receivers and many more. References. [1] J.Corcoran "High Speed Sample and Hold and Analog-to-Digital Converter Circuits",Advances in Analog Circuit Design, April1992. [2] Y.S.Yee,L.M.Terman and L.G.Heller "A lmV MOS comparator," IEEE J. of Solid-State Circuits, vol. SC-13, June 1978. [3] M.Timko and P.Holloway "Circuit Techniques for Achieving High Speed- High Resolution AID Conversion" IEEE Journal of Solid-State Circuits, vol. SC-15, No.6, December 1980. [4] W.H. Gross "New High Speed Amplifier Design, Design Techniques and Layout Problems", Advances in Analog Circuit Design, April 1992. MIXED SIGNAL ASIC DESIGN FOR AUTOMOTIVE AND INDUSTRIAL APPLICATIONS H. Casicr Mietcc Alcatel, Brussels, Belgium ABSTRACT This paper describes the special aspects of mixed signal design in the ASIC environment.The knowledge of the application specific environment and of the function of the ASIC can be used advantageously to lower the cost and to enhance the performance at all levels of design. Several examples of this cost improvement and performance enhancement at device, circuit and system level are shown.