9.07 / November 22, 2016
|Written in||Till version 7: C, After Version 7: Java and Scala|
|Type||Electronic design automation|
|License||GNU General Public License|
The Electric VLSI Design System is an EDA tool written in the early 1980s by Steven M. Rubin. Electric is used to draw schematics and to do integrated circuit layout. It can also handle hardware description languages such as VHDL and Verilog. The system has many analysis and synthesis tools, including Design rule checking, Simulation, Routing, Layout vs. Schematic, Logical Effort, and more.
Electric is currently part of the GNU project and has been developed in Java and distributed as free and open-source software, subject to the requirements of the GNU General Public License (GPL), version 3 or any later.
Alternative Design Style for Integrated Circuits
Unlike other systems that design integrated circuits (ICs) by manipulating polygons on different layers of the wafer, Electric views IC layout as connected circuitry, similar to the way schematic capture systems work. In Electric, designers place nodes (transistors, contacts, etc.) and connect them with arcs (wires). This has advantages and disadvantages.
One advantage is that circuits are always extracted, so analyses that need to know the topology (Layout vs. Schematic, Simulation, etc.) can run faster. Also, by presenting a schematic-capture-like user interface, the system offers a uniform user experience for both IC layout and schematic design. And finally, the nodes-and-arcs view of a circuit makes it easy to add layout constraints to the arcs which allow the designer to "program" the layout so that it stays connected as changes are made.
This style of design also has disadvantages. One disadvantage is that designers are not used to such an interaction and require training in order to use it. It has been observed that people with no previous experience in IC layout are comfortable with Electric's unusual style, but those who have done IC layout on other systems find Electric difficult to use. Another disadvantage is that it is hard to import polygons from traditional systems because they have to be node-extracted, and the polygons don't always match the set of nodes and arcs provided by Electric.
Electric was written in the C programming language in the early 1980s (the earliest internal memo on Electric is dated November 19, 1982). For some time after that, Electric was distributed free of charge to universities and research institutions, and found widespread international use.
In the mid 1980s, Electric was sold commercially by Applicon, under the name "Bravo3VLSI".
In 1988, Electric Editor Incorporated was founded, and sold the system commercially. The company released the source code through the Free Software Foundation in 1998.
In 2000, Static Free Software was created to manage Electric's distribution.
In September, 2003 the C version of Electric was abandoned, and the system was translated into the Java language. The work was completed in June, 2005. Although the C code is still available, it is no longer developed or supported. The new and improved Java code remains free to all users.
- Rubin, Steven M. (1983), "An Integrated Aid for Top-Down Electrical Design", Proceedings, VLSI '83, Anceau and Aas, eds., North Holland, Amsterdam
- Rubin, Steven M. (September 1983), "An Integrated Aid for Top-Down Electrical Design", Proceedings, ICCAD-83, Order No 518, IEEE Computer Society
- Baker, R. Jacob (2010), CMOS Circuit Design, Layout, and Simulation, Third Edition, Wiley-IEEE Press
- Zobrist, George Winston (1989), Progress in Computer-aided VLSI Design: Tools, Ablex Publishing Corporation
- Rubin, Steven M. (1987), Computer Aids for VLSI Design, Addison-Wesley, Reading Massachusetts
- Rubin, Steven M. (1991), "A General-Purpose Framework for CAD Algorithms", IEEE Communications, Special Issue on Communications and VLSI