GNU Electric – An Awesome Free and Open Source Chip VLSI Design Software

GNU Electric is not just another free software, it is a powerful suite of tools that allows users to design schematics, draw circuit diagrams, and ultimately create chip designs at the transistor level as systems design companies do. VLSI.

With its focus on flexibility and efficiency, GNU Electric has become a preferred choice for professionals and enthusiasts alike. In addition, you will find good documentation that will help you with its use and also a good set of libraries for manufacturing the chip in different nodes, test circuits, etc.

What is Electric?

Electric is a computer-aided design system for electrical circuits, with a primary focus on integrated circuit design. However, it is also capable of handling schemas and hardware description languages ​​or HDL (Hardware Description Language) for VLSI (Very Large-Scale Integration) chip design. It is versatile and comprises various technologies, including MOS (nMOS and various variants of CMOS), bipolar and hybrid design. In addition to these IC design technologies, you can work with many other graphical forms, such as schematics, art, FPGA architectures, and more. Includes a built-in technology editor that allows modification and creation of new design environments.

Electric integrates a variety of tools for circuit analysis and synthesis. The system includes design rule checkers, simulators, routers, and much more. Plus, it has an elegant model for tool integration, making it easy to add new ones. Likewise, it has additional tools, such as the IRSIM simulator from Stanford University, which can be perfectly integrated with Electric, as a complement to ALS.

In addition to being able to handle arbitrary technologies and tools, Electric has a powerful interface that provides design constraints and platform portability. The constraint system allows connected components to remain sensibly connected, even when the design is modified. The portability of the platform means that Electric can run on almost any computer (Java code runs anywhere and C code compiles on UNIX/LINUX, Windows and Macintosh). And you will find it available in several languages, including Spanish.

Electric Features

Electric is a highly flexible and powerful VLSI design system that can handle many types of circuit design.. Its sophisticated user interface works on all popular workstations and provides interpretive languages ​​for advanced users. Electric has many analysis and synthesis tools, including design rule checking, simulation, network comparison, routing, compaction, silicon compilation, PLA generation, and compensation.

The verification system design rules Electric monitors all changes made to the design and displays error messages when violations are detected. Electric can also read the output of Assura or Caliber and display the results. The electrical rule checker checks all well and substrate areas for proper contacts and spacing, and performs an antenna rule check for manufacturing validation.

Electric comes with a simulator Built-in 12-state switching level, called ALS. Electric can produce entry decks for a number of popular simulators. Electric users must obtain these simulators on their own.

El PLA CMOS generator from Electric works from a library of PLA elements, allowing for custom dies. The pad frame generator places pad cells around a chip core and connects them together. The ROM generator produces a design from a ROM personality file.

El Electric compactor adjusts geometry to its minimum spacing on the X and Y axes. Logic Effort is a system for marking digital schematic gates with fan-out information that will produce optimally fast circuits. On the other hand, Electric has six experimental placement tools available that use parallelism to speed up the task. Electric's labyrinth router runs individual cables between points. The cell stitching router makes explicit connections where cells join or overlap. The imitation router observes the user's activity and repeats the activity in similar situations throughout the circuit.

El VHDL system Electric can generate VHDL from a layout, and can compile VHDL to netlists of various formats. These netlists can be simulated with the built-in simulator, converted to layout with the silicon compiler, or saved to disk for use by external simulators.

El Electric Silicon Compiler Places and Routes Standard Cells from a list of structural networks, which can be obtained from VHDL, which in turn can be obtained from a schematic drawing. Electric also has a Network Consistency Checker (LVS) tool that compares a design to its equivalent schematic. You can compare two different versions of a design or two different versions of a schematic. An experimental version of NCC is also available, called the Port Exchange Experiment.

And if you want it, you will also have at your disposal a built-in project management system (even a second built-in CVS-based system if you prefer) that allows users to share a library of circuits. Users can extract cells for editing and return them when finished. Other users are prevented from changing the removed cells and can update their circuits when the changes are recorded. Additionally, users are prevented from making changes to checked out cells that would affect other cells that are not checked out. Warnings are also issued when multiple users extract cells that are hierarchically related, which can cause interference with their editing.

As for the supported technologies, we have:

nMOS	Traditional nMOS transistor
CMOS	It comes in several different versions, such as the generic, the Cal Tech Round, or the MOSIS rules
Bipolar	Generic bipolar transistor logic
BiCMOS	Bipolar+CMOS for hybrid circuits
TFT	Thin-film circuits
Digital filters	Generic
PCB	Can support up to 8 layers for printed circuit boards
Schematics	Create schematic circuits with analog and digital components
FPGA	Design for custom FPGA
Artwork	Elements for graphic design

And as for external interfaces, the truth is that Electric is highly file compatible from many other EDAs, for example:

Format	Entrance exit	Description
Tax ID No.	IS	Caltech Intermediate Format
GDS II	IS	Calma GDS Exchange Format
EDIF	IS	Electronic Design Interchange Format
ITS	E	Schematic User Environment
DXF	IS	AutoCAD Native Mechanical Format
VHDL	IS	HDL
verilog	S	HDL
CDL	S	Cadence Description Language
EAGLE	S	Schematic capture
PADS	S	Schematic capture
ECAD	S	Schematic capture
Applicon	E	Applicon/860 (old CAD format)
Bookshelf	E	Bookshelf (placement exchange format)
Tanner	IS	Gerber Scientific (plotter format)
HPGL	S	Plotting Language
PostScript	S	Plotting Language
SVG	S	Scalable Vector Graphics (scalable image for browser)

But this is not all, you can also have plugins like these libraries:

• Boise State: library to use standard cells created by the university they are named after, and based on MOSIS Submicron rules with 3 layers of metallic interconnections and the ability to manufacture the chip in the ON Semiconductor foundry in the C5 process.
• Harvey Mudd: standard cells and chips from Harvey Mudd College, with a 32-bit MIPS microprocessor design and its associated cells.
• MOSIS CMOS- You have both a library for 350nm and 180nm manufacturing technology for pads and standard cells respectively. These libraries were developed by Sun Microsystems Laboratories and the City Engineering College of Bangladesh, guided by Kanada Technologies.
• Sun Microsystems Test Chip: This is a Sun design with around 1 million transistors that was used as a model to measure the structural capacitances of the chip.
• Cell library: another library of cells designed by Hochschule Kempten and used in Electric's Silicon Compiler.

Simply impressive…

GNU Electric: history

The VLSI design software, GNU Electric, has had a long history until what we know today. It was created by Steven M. Rubin in the early 80s and was soon distributed to universities and research institutions around the world. In the mid-80s, Applicon marketed Electric under the name “Bravo3VLSI.” The first Electric designs were written in the C programming language, and can still be downloaded from the official website, although it would later be ported to Java from version 8.0, although 7.0 is maintained based on C if you want it.

In 1988, Electric Editor Incorporated was founded, which sold the system commercially. In 1998, the company released Electric through the Free Software Foundation (GNU). In 1999, Electric development moved to Sun Microsystems.

In 2000, Steven Rubin created Static Free Software, a company that manages the free distribution of Electric. In 2003, the “C” version of Electric was abandoned and its translation into the Java language began, which was completed in 2005. Although the C code is still available, it is no longer developed or supported.

In 2004, Static Free Software became a division of RuLabinsky Enterprises, Incorporated, a corporation that remains dedicated to free software. In 2010, Oracle acquired Sun Microsystems and continued to support the development of Electric until the end of 2016, hence it is based on Java.

In 2017, development of Electric ceased, but Support and bug fixes continue. The code is now available from the Free Software Foundation. It is currently part of the usual repertoire of GNU project packages.

Furthermore, it is currently used by many private hobbyists, and even by professionals. Many universities around the world have used Electric for their chip designs, as have some well-known companies, such as Apple Computer, Intel, Harris Corporation, NEC Electronics, Rambus, Sun Microsystems (now Oracle), and many more. In fact, among the companies that have used it is the famous Transmeta Corporation, the company that developed VLIW microprocessors such as Crusoe and Efficeon, and where Linus Torvalds himself worked when he recently arrived from Finland to Silicon Valley to create Code Morphing, a code that It ran in the background to translate the software's x86 instructions into VLIW to make these chips compatible with everyday software.

How to get free Electric

If you liked it, you can download it for free from here:

• GNU Electric version C, Java and source code for different platforms (Linux, MacOS, Windows).
• Additional Libraries.
• Documentation.
• IRSIM Simulator.