User talk:Rajarajan DEEE

Welcome to all DC circuit equations and laws: Introduction: ”With Electronics Workbench, you can create circuit schematics that look just the same as those you’re already familiar with on paper – plus you can flip the power switch so the schematic behaves like a real circuit. With other electronics simulators,you may have to type in SPICE node lists as text files – an abstract representation of a circuit beyond the capabilities of all but advanced electronics engineers.”(Electronics Workbench User’s guide – version 4, page 7)This introduction comes from the operating manual for a circuit simulation program called Electronics Workbench. Using a graphic interface, it allows the user to draw a circuit schematic and then have the computer analyze that circuit, displaying the results in graphic form. It is every valuable analysis tool, but it has its shortcomings. For one, it and other graphic programs like it tend to be unreliable when analyzing complex circuits, as the translation from picture to computer code is not quite the exact science we would want it to be (yet). Secondly, due to its graphics requirements, it tends to need a significant amount of computational ”horsepower” to run, and a computer operating system that supports graphics. Thirdly, these graphic program scan be costly.However, underneath the graphics skin of Electronics Workbench lies a robust (and free!)program called SPICE, which analyzes a circuit based on a text-file description of the circuitousness and connections. What the user pays for with Electronics Workbench and other graphic circuit analysis programs is the convenient ”point and click” interface, while Spice does the actual mathematical analysis.By itself, SPICE does not require a graphic interface and demands little in system resources.It is also very reliable. The makers of Electronic Workbench would like you to think that using SPICE in its native text mode is a task suited for rocket scientists, but I’m writing this to prove them wrong. SPICE is fairly easy to use for simple circuits, and its non-graphic interface actually lends itself toward the analysis of circuits that can be difficult to draw. I think it was the programming expert Donald Knuth who quipped, ”What you see is all you get”when it comes to computer applications. Graphics may look more attractive, but abstracted interfaces (text) are actually more efficient. History of SPICE SPICE is a computer program designed to simulate analog electronic circuits. original intent was for the development of integrated circuits, from which it derived its name: Simulation Program with Integrated Circuit Emphasis.The origin of SPICE traces back to another circuit simulation program called CANCER. Developed by professor Ronald Roarer of U.C. Berkeley along with some of his students in the late 1960’s, CANCER continued to be improved through the early 1970’s. When Roarer left Berkeley, CANCER was re-written and re-named to SPICE, released as version 1 to the public domain in May of 1972. Version 2 of SPICE was released in 1975 (version 2g6 – the version used in this book – is a minor revision of this 1975 release). Instrumental in the decision to release SPICE as a public-domain computer program was professor Donald Peterson of Berkeley, who believed that all significant technical progress happens when information is freely shared. I for one thank him for his vision.A major improvement came about in March of 1985 with version 3 of SPICE (also released public domain). Written in the C language rather than FORTRAN, version 3 incorporated additional transistor types (the MESFET, for example), and switch elements. Version 3 also allowed the use of alphabetical node labels rather than only numbers. Instructions written for version 2 of SPICE should still run in version 3, though.Despite the additional power of version 3, I have chosen to use version 2 throughout this book because it seems to be the easiest version to acquire and run on different computer systems.