Lesson 6 Circuit Layout Simulation Tool PDF

BACHELOR OF SCIENCE IN COMPUTER ENGINEERING CPE317 – COMPUTER ENGINEERING DRAFTING AND DESIGN LESSON 6 Prepared by: ENGR. SPRINZTSIE MAYE T. GARRUCHA CPE317 Instructor LEARNING OUTCOMES: At the end of this topic, the...

BACHELOR OF SCIENCE IN COMPUTER ENGINEERING CPE317 – COMPUTER ENGINEERING DRAFTING AND DESIGN LESSON 6 Prepared by: ENGR. SPRINZTSIE MAYE T. GARRUCHA CPE317 Instructor LEARNING OUTCOMES: At the end of this topic, the students will be able: 1. To know about the Circuit Layout Simulation Tool and its uses. 2. To have knowledge of the EAGLE and PCB Droid simulators. 3. To create circuits layout that is useful to apply in the bigger project. OUTLINE OF THE TOPIC: 1. Introduction to Circuit Layout Simulation Tool 2. Types, Benefits, List of Common Circuit Layout Simulation Tool 3. Autodesk EAGLE and PCB Droid 1 TOPIC 1: INTRODUCTION TO CIRCUIT LAYOUT SIMULATION TOOL What is Circuit Layout Simulation Tool? Circuit Layout Simulation Tool is a piece of software that emulates the behavior of a real hardware circuit before it is built. The circuit simulator can be used to verify that a hardware design is behaving correctly and producing the desired output signal for a specified set of inputs. Circuit simulation is a process in which a model of an electronic circuit is created and analyzed using various software algorithms, which predict and verify the behavior and performance of the circuit. Since fabrication of electronic circuits, especially integrated circuits (ICs), is expensive and time-consuming, it is faster and more cost-effective to verify the behavior and performance of the circuit using a circuit simulator before fabrication. There are different types of circuit simulators catering to varied needs across the accuracy- performance/capacity spectrum. At one end of the spectrum are analog simulators that solve accurate representations of the electronic circuits. They offer high accuracy and are commonly used to simulate small circuits. At the other end of the spectrum are digital simulators that use functional representations of electronic circuits, typically described using hardware description languages (HDL). These offer the highest performance and capacity, but at relatively lower levels of accuracy. Digital simulators are commonly used to simulate very large circuits. Analog devices’ design tools simplify your design and product selection process through ease of use and by simulating results that are optimized and tested for accuracy. Analog devices circuit design tools are web based or downloadable but not always free to use. They also do the following: Reduce your testing time and get to the finished product faster Overcome engineering challenges and simplify calculations Use industry leading products to create the best design Be confident in the results and your solution A circuit diagram (electrical diagram, elementary diagram, electronic schematic) is a graphical representation of an electrical circuit. A pictorial circuit diagram uses simple images of components, while a schematic diagram shows the components and interconnections of the circuit using standardized symbolic representations. The presentation of the interconnections between circuit components in the schematic diagram does not necessarily correspond to the physical arrangements in the finished device. Unlike a block diagram or layout diagram, a circuit diagram shows the actual electrical connections. A drawing meant to depict the physical arrangement of the wires and the components they connect is called artwork or layout, physical design, or wiring diagram. Circuit diagrams are used for the design (circuit design), construction (such as PCB layout), and maintenance of electrical and electronic equipment. 2 Symbols Circuit diagrams are pictures with symbols that have differed from country to country and have changed over time but are now to a large extent internationally standardized. Simple components often had symbols intended to represent some feature of the physical construction of the device. For example, the symbol for a resistor shown here dates back to the days when that component was made from a long piece of wire wrapped in such a manner as to not produce inductance, which would have made it a coil. These wires wound resistors are now used only in high-power applications, smaller resistors being cast from carbon composition (a mixture of carbon and filler) or fabricated as an insulating tube or chip coated with a metal film. The internationally standardized symbol for a resistor is therefore now simplified to an oblong, sometimes with the value in ohms written inside, instead of the zig-zag symbol. A less common symbol is simply a series of peaks on one side of the line representing the conductor, rather than back-and-forth as shown here. Wire Crossover Symbols for Circuit Diagrams. The CAD symbol for insulated crossing wires is the same as the older, non-CAD symbol for non-insulated crossing wires. To avoid confusion, the wire "jump" (semi-circle) symbol for insulated wires in non-CAD schematics is recommended (as opposed to using the CAD-style symbol for no connection), so as to avoid confusion with the original, older style symbol, which means the exact opposite. The newer, recommended style for 4-way wire connections in both CAD and non-CAD schematics is to stagger the joining wires into T-junctions. The linkages between leads were once simple crossings of lines. With the arrival of computerized drafting, the connection of two intersecting wires was shown by a crossing of wires with a "dot" or "blob" to indicate a connection. At the same time, the crossover was simplified to be the same crossing, but without a "dot". However, there was a danger of confusing the wires that were connected and not connected in this manner, if the dot was drawn too small or accidentally omitted 3 (e.g. the "dot" could disappear after several passes through a copy machine). As such, the modern practice for representing a 4-way wire connection is to draw a straight wire and then to draw the other wires staggered along it with "dots" as connections (see diagram), so as to form two separate T-junctions that brook no confusion and are clearly not a crossover. For crossing wires that are insulated from one another, a small semi-circle symbol is commonly used to show one wire "jumping over" the other wire (similar to how jumper wires are used). A common, hybrid style of drawing combines the T-junction crossovers with "dot" connections and the wire "jump" semi-circle symbols for insulated crossings. In this manner, a "dot" that is too small to see or that has accidentally disappeared can still be clearly differentiated from a "jump". On a circuit diagram, the symbols for components are labelled with a descriptor or reference designator matching that on the list of parts. For example, C1 is the first capacitor, L1 is the first inductor, Q1 is the first transistor, and R1 is the first resistor. Often the value or type designation of the component is given on the diagram beside the part, but detailed specifications would go on the parts list. Detailed rules for reference designations are provided in the International standard IEC 61346. Comparison of pictorial and schematic styles of circuit diagrams. Common schematic diagram symbols (US symbols) 4  The circuit diagram for a four-bit TTL counter, a type of state machine Organization It is a usual although not universal convention that schematic drawings are organized on the page from left to right and top to bottom in the same sequence as the flow of the main signal or power path. For example, a schematic for a radio receiver might start with the antenna input at the left of the page and end with the loudspeaker at the right. Positive power supply connections for each stage would be shown towards the top of the page, with grounds, negative supplies, or other return paths towards the bottom. Schematic drawings intended for maintenance may have the principal signal paths highlighted to assist in understanding the signal flow through the circuit. More complex devices have multi-page schematics and must rely on cross-reference symbols to show the flow of signals between the different sheets of the drawing. Detailed rules for the preparation of circuit diagrams, and other document types used in electro technology, are provided in the international standard IEC 61082-1. Relay logic line diagrams, also called ladder logic diagrams, use another common standardized convention for organizing schematic drawings, with a vertical power supply rail on the left and another on the right, and components strung between them like the rungs of a ladder. Artwork Once the schematic has been made, it is converted into a layout that can be fabricated onto a printed circuit board (PCB). Schematic-driven layout starts with the process of schematic capture. The result is what is known as a rat's nest. The rat's nest is a jumble of wires (lines) crisscrossing each other to their destination nodes. These wires are routed either manually or automatically by the use of electronic design automation (EDA) tools. The EDA tools arrange and rearrange the placement of components and find paths for tracks to connect various nodes. This results in the final layout artwork for the integrated circuit or printed circuit board. 5 A generalized design flow may be as follows: Schematic → schematic capture → netlist → rat's nest → routing → artwork → PCB development and etching → component mounting → testing A rat's nest Simulation of PCB Simulation of electronic circuit uses mathematical models to get the actual behavior of the printed circuit board or electronic devices. Simulation software allows for modeling of electronic circuit operation. Simulating a circuit behavior before actually manufacturing it improves the design efficiency. In integrated circuits the manufacturing cost is very much high, internal signals behavior is difficult. Simulator involves schematic editor, simulation engine, and waveform display and sees what effect can occur during operation. Printed circuit boards designing require specific modeling such as transmission lines, IBIS models for running and receiving electronics. Simulation is an essential process of design of any component or machine. In the designing process of printed circuit boards, there are a lot of simulators available or free software PCB design software. It basically increases the efficiency of manufacturing by providing a fast preview to say how printed circuit board is going to look like and also up to some extent promise the performance of the printed circuit board in application. If PCB has any kind of functional property involving speed, frequency, signals, lower current then it is required to get the best schematic layout to integrate the system with better simulation tools. Power delivery, signal integrity, mixed signal simulation and many other parameters can be analyzed very easily very easily by simulating the Printed circuit board. 6 TOPIC 2: TYPES, BENEFITS, LIST OF COMMON CIRCUIT LAYOUT SIMULATION TOOL Types of Circuit Simulation There are three basic types of circuit simulation: analog, digital, and mixed-mode. Analog circuit simulation involves the use of highly accurate models (i.e., representations) of the electronic circuit to achieve high accuracy. The models include non-linear, linear, and simpler table-based representations of the various electronic devices in the circuit. Analog simulation can run in different modes. These include AC (frequency domain), DC (non-linear quiescent), and transient (time-domain). All analog simulators employ algorithms to mathematically analyze the behavior of the electronic circuit in these different modes. They all share the quality of solving matrices to predict the performance of the electronic circuit. Signals are propagated as continuously varying values. There are two primary types of analog circuit simulators: SPICE and FastSPICE. SPICE simulators use highly accurate non-linear and linear models of electronic devices to analyze the behavior of the circuit. SPICE simulators employ many different integration methods, such as Forward Euler, Backward Euler, and Newton-Raphson as well as matrix decomposition techniques to compute the response of the entire circuit (i.e., mathematical representation) at every single time point in the simulation period of interest. SPICE - Simulation Program with Integrated Circuit Emphasis. By contrast, FastSPICE simulators use simpler table-model representations of electronic devices to analyze circuit behavior. They employ sophisticated algorithms to reduce the complexity of the circuit and partition the circuit based on various criteria, essentially creating a simpler and more modular circuit representation. This representation is then selectively evaluated at a given time point in the simulation period of interest, a process that greatly improves the performance and capacity of the simulation. FastSPICE simulators offer various simulation knobs to help balance the tradeoffs between simulation accuracy and performance. Digital circuit simulation involves the use of simpler models of the electronic circuit. These models are typically created using HDL (Hardware Description Language). In digital simulation, rather than propagating continuously varying signals, a few discrete voltage levels (primarily logic 0 and logic 1) are propagated. The methods to propagate these signals have varying degrees of accuracy regarding the propagation delay of the logic levels through the circuit. This method of simulation allows much larger circuits to be simulated in less time with fewer compute resources when compared to analog simulation. Mixed-mode circuit simulation combines the analog and digital simulation approaches. The circuit is partitioned between the two regimes to support the correct level of analysis detail for each part of the circuit. Analog simulators (SPICE and FastSPICE) are used for the analog analyses and a digital simulator is used for the digital analyses. This method of simulation allows for much larger circuits to be simulated in less time with fewer compute resources when compared to analog simulation. 7 Benefits of Circuit Simulation Circuit simulation provides a critical view into the behavior of electronic circuits. Given the expense and time involved in fabricating electronic circuits, especially ICs, it’s much more practical to validate circuit behavior and performance via circuit simulation prior to manufacturing. Some of the specific areas of validation include: Memory Performance. The read and write access times and latency of memory devices are built from analog circuit simulation of the bit cells and read/write paths inside these memories. Overall Digital Simulation Accuracy. Digital circuit simulators model the propagation of voltage for logic level 1 and logic level 0. Analog circuit simulation is used to determine the time it takes for a circuit to transition between these voltage levels. This forms the basis for the overall accuracy of the digital circuit simulator. Noise and Crosstalk. Higher level models for noise and crosstalk are developed based on the detailed circuit level analysis of these parasitic effects from analog circuit simulations. Optimization of High-Frequency and High-Power Circuits. These types of circuits must undergo detailed continuous time analysis to determine their behavior and performance criteria. Analog circuit simulation delivers these important analyses. The overall performance and behavior of complex digital circuits. Core processors and AI accelerators as examples, are verified with digital circuit simulation. List of Common Circuit Layout Simulation Tool Circuit Simulation software comes in handy while designing and testing complex systems in a cost-effective manner. But, it is challenging to choose the best circuit simulation software, given the vast number of options that range from free software to paid ones. 1. Autodesk Eagle The software utilizes the Ngspice tools to run its circuit simulations. Other than the simulation capabilities, this software offers a PCB editor capable of designing up to 16 layers of PCB with board sizes up to 4m^2. This software is generally used by small electronic makers, hobbyists, and industry experts. The layout is user-friendly since there exists a large community, resources, and tutorials on how to use it. https://www.autodesk.com/products/eagle/free-download 2. PCB Droid PCB Droid provides an easy way to design your printed circuit boards for your electronic DIY projects. It can be an extension hardware for your raspberry PI or Arduino panel, or even a printed circuit board for the drone or 3d printer you designed. Create your custom PCBs on your mobile and on your tablet fast and efficiently. Share and export your finished designs. Save time by working on your projects during your daily commute, no matter where you are. https://play.google.com/store/apps/details?id=com.theophrast.droidpcb&hl=en&gl=US 8 3. NI Multisim This software is majorly used by education institutions for teaching and research of analog, digital, and power electronic circuitry. It uses the original SPICE-based simulation software that gives highly accurate results that are comparable to real-world testing. https://www.ni.com/en-ph/shop/electronic-test-instrumentation/application-software-for- electronic-test-and-instrumentation-category/what-is-multisim.html 4. LTspice This software comes with a highly reputable SPICE simulator coupled with a waveform capture and schematic capture platform. It’s a free software with no hidden costs but comes with a restriction that users are not allowed to work with Analog device products. This software comes packed with an advanced algorithm that enables it to carry out simulations faster than most paid circuit simulation software. https://www.analog.com/en/design-center/design-tools-and-calculators/ltspice- simulator.html 5. PSIM This is a simulation software that specializes in the simulation of power electronics and motor drives. The software is not limited to these functions since it can also simulate other electronic circuitry. It has an embedded code generator as well as a thermal simulation to compute switching and conduction losses of switching devices. https://powersimtech.com/products/psim/capabilities-applications/ 6. EasyEDA This is a web-based EDA tool kit with a simulation and is fully functional. It is ideal for students and hobbyists since it does not have any commercial licenses. It can generate a BOM, has a PCB editor, and is capable of converting schematics into a PCB. It is one of the cheapest simulation software offering three packages. https://easyeda.com/ 7. KiCAD KiCAD is free software with some added advantages. You can modify the software to your liking by editing the source code. It comes with a 3D viewer that allows visualization of PCB. It runs simulations using the ‘ngspice’ which is a free SPICE tool. It is great for making PCB layouts since it does not have a limit to the board size, number of pins, or number of layers. https://www.kicad.org/ 8. CEDAR Logic Simulator This is an open-source circuit design and simulation software. It can be used for circuit simulation, analysis, and design. It allows you to create circuits from a variety of devices such as resistors, capacitors, inductors, diodes, transistors (BJT and FET), op amps, comparators and Z80 microprocessors. https://cedar-logic-simulator.apponic.com/ 9 9. Tina TI Tina-TI is a free circuit simulation software that is not only capable of designing and simulating circuits but also allows you to check the circuit for errors before running the simulation. On top of this, you are able to perform DC, AC, Transient, and Fourier analysis. You will also find almost all the components that you need for circuit design. https://www.ti.com/tool/TINA-TI 10. idealCircuit This software is capable of both electrical and electronic circuit simulation. You can load a design circuit in the ‘.ic’ format for simulation. https://sidelinesoft.com/ic/ 11. Proteus It is the best available paid circuit simulation software. It is feature packed with over 15 million parts in its component library, as well as features like Raspberry Pi microcontrollers, group length matching, differential pair routing, and remote front panel design for Arduino just to mention a few. This software is capable of handling design and simulations with ease due to its refined features over the years. https://www.labcenter.com/simulation/ 12. Fritzing Fritzing is an open-source hardware initiative that makes electronics accessible as a creative material for anyone. We offer a software tool, a community website and services in the spirit of Processing and Arduino, fostering a creative ecosystem that allows users to document their prototypes, share them with others, teach electronics in a classroom, and layout and manufacture professional PCBs. https://fritzing.org/ 13. Circuit Maker CircuitMaker is the best free-to-use schematic and PCB design tool for the Open Source Hardware community. We think that just because you’re willing to share your work and passion for electronics, doesn’t mean you should have to use second-rate design tools. We think, that if you’re giving back to the community, you deserve something that will help, not hinder. But CircuitMaker is more than just a free schematic and PCB design tool - it’s a vibrant community of open source designers, makers, hobbyists, students and professionals working together to make exciting new products every day. https://circuitmaker.com/ 14. Open Circuit Design PCB is free software for designing printed circuit board layouts. It has many features and is capable of professional-quality output. It is available for UN*X operating systems, e.g., GNU/Linux, Mac OS-X, or Cygwin under Windows. pcb was orignally written by Thomas Nau of the University of Ulm, Germany, and is now maintained by harry eaton of the Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland, USA. http://opencircuitdesign.com/pcb/index.html 10 15. ADS Circuit Design Software Advanced Design System (ADS) is an electronic design automation software system produced by PathWave Design, a division of Keysight Technologies. It provides an integrated design environment to designers of RF electronic products such as mobile phones, pagers, wireless networks, satellite communications, radar systems, and high- speed data links. Keysight ADS supports every step of the design process — schematic capture, layout, design rule checking, frequency-domain and time-domain circuit simulation, and electromagnetic field simulation — allowing the engineer to fully characterize and optimize an RF design without changing tools. https://www.keysight.com/us/en/products/software/pathwave-design-software/pathwave- advanced-design-system.html 16. nagaEDA Circuit Design Software naga EDA devotes to provide useful electronic design tools in C++ and, especially, Python. The current release contains naga.Verilog, a Verilog parser. Please visit project homepage http://naga-eda.org/ 17. OpenSce Circuit Design Software This project aims to create a multiplatform opensource software which allows both the design and the characterization of electronical linear circuits, using either a command-line interface or an attractive GUI. It will replace professional software which may be either closed, expensive, too complex for education usage, or dedicated to specific software products (from either Texas Instruments, MicroChip, Linear Technology...). https://opensce.sourceforge.net/ 18. QSapecNG Circuit Design Software QSapecNG is a Qt-based program for symbolic analysis of linear analog circuits. In fact, it consists of two independent parts: the SapecNG framework and the GUI of the application, QSapecNG. It is an open source, multi-platform project, continuously enhanced by students and researchers of Department of Electronics and Telecommunications of the University of Florence. https://qsapecng.sourceforge.net/ 19. Simulide Super SimulIDE is a simple real time electronic circuit simulator, intended for hobbyist or students to learn and experiment with simple electronic circuits and microcontrollers, supporting PIC, AVR and Arduino. https://www.simulide.com/p/home.html 20. Gerbv Gerbv is a viewer for Gerber RS-274X files, Excellon drill files, and CSV pick-and-place files. Gerber files are typically output by a PCB CAD tool (such as the gEDA Project's PCB), and are sent to a PCB manufacturer who uses the files for manufacturing Printed Circuit Boards (PCBs). Gerbv is free/open-source software. http://gerbv.geda-project.org/ 11 TOPIC 3: AUTODESK EAGLE AND PCB DROID What is EAGLE? EAGLE is electronic design automation (EDA) software that lets printed circuit board (PCB) designers seamlessly connect schematic diagrams, component placement, PCB routing, and comprehensive library content. Eagle stands for Easily Applicable Graphical Layout Editor. Features of EAGLE Schematic editor o SPICE simulator – Quickly test ideas and validate circuit performance with SPICE simulation methods. o Modular design blocks – Drag and drop reusable design blocks between your projects, complete with synchronized schematic and PCB circuitry. o Electronic rule checking – Validate your schematic design with a complete set of electronic rule checks, so your schematic can stay on track. PCB layout editor o Real-time design synchronization – All changes stay automatically in sync between your schematic and layout, so you can focus on the creative process. o Intuitive alignment tools – Precisely arrange and order PCB design objects with a complete set of alignment tools. o Push and shove routing – Adhere to all your design rules while the adaptive interactive router pushes and shoves your PCB traces. o Obstacle avoidance routing – Route complex PCB layouts and maneuver around your design to easily get your trace to its destination. o New routing engine – Create PCB layouts quickly. Explore tools for loop removal, cornering, and via placement while routing. o Design rule checking (DRC) – User interface in EAGLE with the DRC (design rule checking). Control your design flow and avoid unexpected surprises with fully customizable PCB design rules and constraints. PCB library content o Managed online libraries – Worry-free libraries are ready for your next design. Find and place parts dynamically linked to the growing catalog. o 3D PCB models – Don’t rely on luck to fit your board in its enclosure. Accurate 3D models enable the PCB to fit the first time. o Complete components – Out-of-the-box component libraries include symbol, footprint, 3D model, and parametrics. 12  PCB community o One-click make – PCB manufacturing without the headache. Push complete outputs to the hub, connecting with your manufacturer directly. o Fusion 360 integration – Design the PCB object directly in Fusion 360 and synchronize bidirectional changes to your PCB design seamlessly. o User language programs (ULPs) – Enhance usability and capabilities with one of the scripts or programs created by the vast online PCB community. Software Download Free download PCB design software for everyone. Included with a Fusion 360 for personal use subscription, EAGLE free download is a limited version for hobbyists including 2 schematic sheets, 2 signal layers, and an 80cm2 (12.4in2) board area. It is available for Windows, Mac, and Linux operating system. Download link: https://www.autodesk.com/products/eagle/free-download What is PCB DROID? PCB Droid is a mobile application that provides an easy way to design a printed circuit boards for electronic DIY projects. It can be an extension hardware for Raspberry PI or Arduino panel, or even a printed circuit board for the drone or 3D printer designed. Allows to create a custom PCBs on mobile and on tablet fast and efficiently. Share and export finished designs. Save time by working on the projects during the daily commute conveniently. PCB Droid’s easy to use experience makes the application the perfect choice for electronic hobbyists and also a great designer tool for education purposes. The application doesn’t utilize previously made circuit diagrams. Draw your lines, place your through holes and SMD pads the way you want to. Download the available macros to help your designing process or create your own and use them later on. Log in with your own PCB Droid account or use your Gmail account and start customizing your circuit boards as you wish! If you are having trouble using the application, check out the official tutorial on the website. http://pcbdroid.com/tutorials/ Features of PCB DROID Design double-sided PCBs, switch between layers, hide the unnecessary layers for improved transparency. Expanding downloadable component library. Create and save your own macros. Share your finished printed circuit boards with your friends/colleagues. Export your projects to PDF, IMG or GERBER format. Reach your project from multiple devices with droid cloud integration. 13 Application Download PCB Droid is available to Google Play or visit the link: https://play.google.com/store/apps/details?id=com.theophrast.droidpcb&hl=en&gl=US Reference: https://www.synopsys.com/glossary/what-is-circuit-simulation.html https://www.autodesk.com/products/eagle/overview https://play.google.com/store/apps/details?id=com.theophrast.droidpcb&hl=en&gl=US https://www.raypcb.com/simulation-of-pcb/ https://www.etechnophiles.com/best-circuit-simulation-software/ 14