CMOS Integrated Circuit Simulation with LTspice IV a Tutorial Guide Erik Bruun Download free books at Erik Bruun CMOS Integrated Circuit Simulation with LTspice IV – a Tutorial Guide Download free eBooks at bookboon.com CMOS Integrated Circuit Simulation with LTspice IV – a Tutorial Guide 1st edition © 2015 Erik Bruun & bookboon.com ISBN 978-87-403-1059-7 Peer reviewed by Dennis Øland Larsen, IC design engineer, GN ReSound Download free eBooks at bookboon.com CMOS Integrated Circuit Simulation with LTspice IV – a Tutorial Guide Contents Contents Preface Getting started Tutorial – Resistive Circuits Example 1.1: A resistor circuit Example 1.2: A transconductance amplifier Example 1.3: A current amplifier Problems Tutorial – Circuits with Capacitors and Inductors Example 2.1: An RC network Example 2.2: A half-wave rectifier with a smoothing filter Example 2.3: An amplifier with capacitive feedback network Example 2.4: An ideal inductor Example 2.5: Revisiting the capacitor charging and discharging Problems Tutorial – MOS transistors Example 3.1: Different MOS transistor symbols and models in LTspice Example 3.2: Advanced transistor models Example 3.3: MOS transistor input characteristics Example 3.4: MOS transistor output characteristics Example 3.5: Deriving transistor parameters from input and output characteristics Example 3.6: Simulating small signal parameters using the ‘.tf’ simulation Problems Download free eBooks at bookboon.com 13 13 27 32 38 43 43 50 52 55 57 63 67 67 75 79 84 86 90 98 CMOS Integrated Circuit Simulation with LTspice IV – a Tutorial Guide Contents Tutorial – Basic gain stages Example 4.1: The common source amplifier (inverting amplifier) Example 4.2: The common drain amplifier (source follower) Example 4.3: The common gate amplifier Example 4.4: The differential pair Problems 103 103 114 121 126 140 147 147 154 165 168 175 179 180 187 196 198 206 Tutorial – Hierarchical design Example 5.1: A two stage operational amplifier Example 5.2: Designing the two stage opamp for an inverting feedback amplifier Example 5.3: Generic filter blocks Example 5.4: A mixed analog/digital circuit Problems Tutorial – Process and parameter variations Example 6.1: Model files for corner simulations Example 6.2: An inverter Example 6.3: A test bench for the two stage opamp Example 6.4: Monte Carlo simulation Problems www.sylvania.com We not reinvent the wheel we reinvent light Fascinating lighting offers an ininite spectrum of possibilities: Innovative technologies and new markets provide both opportunities and challenges An environment in which your expertise is in high demand Enjoy the supportive working atmosphere within our global group and beneit from international career paths Implement sustainable ideas in close cooperation with other specialists and contribute to inluencing our future Come and join us in reinventing light every day Light is OSRAM Download free eBooks at bookboon.com Click on the ad to read more CMOS Integrated Circuit Simulation with LTspice IV – a Tutorial Guide Contents Tutorial – Importing and exporting files Example 7.1: Importing a netlist file describing a current conveyor Example 7.2: Creating a subcircuit from a netlist Example 7.3: Exporting a netlist Example 7.4: Exporting other files Problems 211 211 215 221 223 227 Moving on 231 Appendix A – A beginner’s guide to components and simulation commands in LTspice 233 Appendix B – BSIM transistor models for use in LTspice 241 Index 245 360° thinking Discover the truth at www.deloitte.ca/careers Download free eBooks at bookboon.com © Deloitte & Touche LLP and affiliated entities Click on the ad to read more CMOS Integrated Circuit Simulation with LTspice IV – a Tutorial Guide Preface Preface This book is about circuit simulation with the simulation program LTspice It is intended as an introduction to LTspice and to simulation of CMOS integrated circuits with LTspice It may serve as a supplementary textbook for an introductory course in analog integrated circuit design The first tutorials can also be used as a general introduction to circuit simulation in an introductory course in electronic circuits The book can be used for classroom teaching, and it can also be used for self-study It is based on LTspice for Windows Tutorials and introduce the fundamental concept of the circuit simulator demonstrated on circuits using passive devices (resistors, capacitors and inductors) and ideal voltage sources and current sources, both independent sources and controlled sources Download free eBooks at bookboon.com CMOS Integrated Circuit Simulation with LTspice IV – a Tutorial Guide Preface Tutorial is about MOS transistor models and gives an introduction to the standard ShichmanHodges transistor model often used for hand calculations when analyzing CMOS circuits Also, it provides an introduction to more advanced transistor models and a comparison between the advanced transistor models and the simple Shichman-Hodges model Tutorial gives examples of basic CMOS amplifier stages, i.e common source, common drain, common gate and differential pair Both analysis and design approaches using LTspice are shown Tutorial shows how the basic stages can be defined as subcircuits and combined into a multistage operational amplifier Also given in this tutorial is a design example of a two stage opamp for a feedback amplifier, generic filter blocks and a mixed analog/digital circuit The tutorial is an introduction to hierarchical design Tutorial is about the simulation of process and parameter variations in a circuit In integrated circuit design, process variations pose a major challenge to the designer Often technology files are supplied for typical process parameters and a selection of worst case process parameters The tutorial gives an introduction to simulation with technology files including process variations Also supply voltage variations and temperature variations are considered Together, these variations are termed PVT variations Tutorial is about import of netlist files and export of output files from LTspice The netlist files are the primary descriptive files for a circuit to be simulated by Spice There are minor differences between netlist files originating from LTspice and other versions of Spice, but in general it is rather straightforward to modify a netlist file to be compatible with LTspice Several textbooks provide examples of netlist files which may be used for simulation with LTspice A schematic is not needed The simulation commands in LTspice can be executed directly from the netlist files End-of-chapter problems are provided for all tutorials to further illustrate the subject of the tutorials Finally, two appendices are included Appendix A is a beginner’s guide which may facilitate quick and easy learning of LTspice for the reader or student who is new to LTspice Appendix B provides a number of BSIM transistor model files for use in LTspice The files may be copied directly from the electronic version of this book into a text editor Acknowledgements: The author would like to acknowledge the many students who have contributed with comments and suggestion for the book Also, a particular acknowledgement goes to my colleague Dennis Øland Larsen who reviewed the entire manuscript and provided many useful comments and corrections during the final phase of writing Download free eBooks at bookboon.com CMOS Integrated Circuit Simulation with LTspice IV – a Tutorial Guide Getting started Getting started The program LTspice is freely available from Linear Technology, http://www.linear.com/designtools/software/ Just click ‘Download LTspice’ and follow the instructions You may register for an account with Linear Technology, but you not have to You may just click ‘No thanks, just download the software’ and choose ‘Run’ in the dialogue box which appears A ‘Getting started guide’ is available from http://cds.linear.com/docs/en/software-and-simulation/LTspiceGettingStartedGuide.pdf This book is addressing the simulation of integrated circuits, in particular CMOS circuits, so we will not go into detail with the simulation of circuits with standard components but refer the reader to the many examples of demo circuits using standard components which are found on the LTspice website Here you will also find a blog with several hints and video clips on how to use LTspice Download free eBooks at bookboon.com CMOS Integrated Circuit Simulation with LTspice IV – a Tutorial Guide Getting started In addition, comprehensive books and guides about Spice can be found, (Tuinenga 1995) and (Vladimirescu 1994), and a manual dedicated to LTspice is also available (Brocard 2013) However, the program is fairly easy and intuitive and once the installation is complete, you may go directly to the first tutorial, providing you with examples of circuits using resistors, voltage sources and current sources A ‘learning by doing’ approach is perfectly feasible with LTspice The program also includes a ‘help’ function with detailed descriptions of the commands and options in the program The keyboard shortcut to ‘help’ is ‘F1’ in the windows version and ‘ ?’ in the Mac version If you want a paper manual for the program, you can get it using the ‘help’ function: Just open ‘help’, click on the ‘Print’ symbol and select ‘Print the selected heading and all subtopics’ in the dialogue box which opens Your printer should be ready for printing about 130 pages This book is based on the Windows version of LTspice The program is also available for Mac There are some differences in the user interface of the two versions This might be somewhat confusing for first-time users As a guide to Mac users, the following page provides a list of some of the differences which may initially cause confusion 10 Download free eBooks at bookboon.com ...Erik Bruun CMOS Integrated Circuit Simulation with LTspice IV – a Tutorial Guide Download free eBooks at bookboon.com CMOS Integrated Circuit Simulation with LTspice IV – a Tutorial Guide... the ad to read more CMOS Integrated Circuit Simulation with LTspice IV – a Tutorial Guide Preface Preface This book is about circuit simulation with the simulation program LTspice It is intended... bookboon.com CMOS Integrated Circuit Simulation with LTspice IV – a Tutorial Guide Contents Contents Preface Getting started Tutorial – Resistive Circuits Example 1.1: A resistor circuit