Filename extension | .gds |
---|---|
Developed by | Calma |
Initial release | 1989 |
Type of format | binary [1] |
Free format? | no |
GDSII stream format (GDSII), is a binary database file format which is the de facto industry standard for Electronic Design Automation data exchange of integrated circuit or IC layout artwork. [1] It is a binary file format representing planar geometric shapes, text labels, and other information about the layout in hierarchical form (two-dimensional/2D CAD file format). The data can be used to reconstruct all or part of the artwork to be used in sharing layouts, transferring artwork between different tools, or creating photomasks.
GDS = Graphic Design System (see [GDS78])
Initially, GDSII was designed as a stream format used to control integrated circuit photomask plotting. Despite its limited set of features and low data density, it became the industry conventional stream format for transfer of IC layout data between design tools of different vendors, all of which operated with proprietary data formats.
It was originally developed by Calma for its layout design system, "Graphic Design System" ("GDS") and "GDSII".
GDSII files are usually the final output product of the IC design cycle and are handed over to IC foundries for IC fabrication. GDSII files were originally written on magnetic tape. The final deadline for IC designers is still called tape-out for this reason.
Objects contained in a GDSII file are grouped by assigning numeric attributes to them including a "layer number", "datatype" or "texttype". While these attributes were designed to correspond to the "layers of material" used in manufacturing an integrated circuit, their meaning rapidly became more abstract to reflect the way that the physical layout is designed.
As of April 2008, many EDA software vendors have moved to the stream format OASIS, which replaced GDSII. [2]
As the GDSII stream format is a de facto standard, it is supported by nearly all EDA software. Besides the commercial vendors there are plenty of free GDSII utilities. These free tools include editors, [3] [4] [5] viewers, [6] utilities to convert the 2D layout data into common 3D formats, [7] [8] utilities to fly through a 3D version, [9] utilities to convert the binary format to a human readable ASCII format [10] and program libraries. [11] [12] [13]
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: CS1 maint: archived copy as title (link) CS1 maint: bot: original URL status unknown (link)A file viewer is a utility application software on operating systems, such as Linux, macOS, or Windows. The file viewer is responsible for user access of files located on a data storage device. File viewers allow the user to open and view content on a device, such as a Personal Computer (PC) or a mobile phone.
Electronic design automation (EDA), also referred to as electronic computer-aided design (ECAD), is a category of software tools for designing electronic systems such as integrated circuits and printed circuit boards. The tools work together in a design flow that chip designers use to design and analyze entire semiconductor chips. Since a modern semiconductor chip can have billions of components, EDA tools are essential for their design; this article in particular describes EDA specifically with respect to integrated circuits (ICs).
In integrated circuit design, integrated circuit (IC) layout, also known IC mask layout or mask design, is the representation of an integrated circuit in terms of planar geometric shapes which correspond to the patterns of metal, oxide, or semiconductor layers that make up the components of the integrated circuit. Originally the overall process was called tapeout, as historically early ICs used graphical black crepe tape on mylar media for photo imaging.
Open Artwork System Interchange Standard (OASIS) is a binary file format used for specification of data structures for photomask production. It's used to represent a pattern an interchange and encapsulation format for hierarchical integrated circuit mask layout information produced during integrated circuit design that is further used for manufacturing of a photomask. The standard is developed by SEMI. The language defines the code required for geometric shapes such as rectangles, trapezoids, and polygons. It defines the type of properties each can have, how they can be organized into cells containing patterns made by these shapes and defines how each can be placed relative to each other. It is similar to GDSII.
Calma Company, based in Sunnyvale, California, was, between 1965 and 1988, a vendor of digitizers and minicomputer-based graphics systems targeted at the cartographic and electronic, mechanical and architectural design markets.
CATS is an EDA software for mask data preparation (MDP) in integrated circuit design and manufacturing.
Place and route is a stage in the design of printed circuit boards, integrated circuits, and field-programmable gate arrays. As implied by the name, it is composed of two steps, placement and routing. The first step, placement, involves deciding where to place all electronic components, circuitry, and logic elements in a generally limited amount of space. This is followed by routing, which decides the exact design of all the wires needed to connect the placed components. This step must implement all the desired connections while following the rules and limitations of the manufacturing process.
In electronic design automation, a design rule is a geometric constraint imposed on circuit board, semiconductor device, and integrated circuit (IC) designers to ensure their designs function properly, reliably, and can be produced with acceptable yield. Design rules for production are developed by process engineers based on the capability of their processes to realize design intent. Electronic design automation is used extensively to ensure that designers do not violate design rules; a process called design rule checking (DRC). DRC is a major step during physical verification signoff on the design, which also involves LVS checks, XOR checks, ERC, and antenna checks. The importance of design rules and DRC is greatest for ICs, which have micro- or nano-scale geometries; for advanced processes, some fabs also insist upon the use of more restricted rules to improve yield.
OpenSceneGraph is an open-source 3D graphics application programming interface, used by application developers in fields such as visual simulation, computer games, virtual reality, scientific visualization and modeling.
An image file format is a file format for a digital image. There are many formats that can be used, such as JPEG, PNG, and GIF. Most formats up until 2022 were for storing 2D images, not 3D ones. The data stored in an image file format may be compressed or uncompressed. If the data is compressed, it may be done so using lossy compression or lossless compression. For graphic design applications, vector formats are often used. Some image file formats support transparency.
Mask data preparation (MDP), also known as layout post processing, is the procedure of translating a file containing the intended set of polygons from an integrated circuit layout into set of instructions that a photomask writer can use to generate a physical mask. Typically, amendments and additions to the chip layout are performed in order to convert the physical layout into data for mask production.
An EDA database is a database specialized for the purpose of electronic design automation. These application specific databases are required because general purpose databases have historically not provided enough performance for EDA applications.
iXML is an open standard for the inclusion of location sound metadata in Broadcast Wave audio files, video files and also IP video and audio streams. This includes things like Scene, Take and Notes information.
A process design kit (PDK) is a set of files used within the semiconductor industry to model a fabrication process for the design tools used to design an integrated circuit. The PDK is created by the foundry defining a certain technology variation for their processes. It is then passed to their customers to use in the design process. The customers may enhance the PDK, tailoring it to their specific design styles and markets. The designers use the PDK to design, simulate, draw and verify the design before handing the design back to the foundry to produce chips. The data in the PDK is specific to the foundry's process variation and is chosen early in the design process, influenced by the market requirements for the chip. An accurate PDK will increase the chances of first-pass successful silicon.
In the automated design of integrated circuits, signoff checks is the collective name given to a series of verification steps that the design must pass before it can be taped out. This implies an iterative process involving incremental fixes across the board using one or more check types, and then retesting the design. There are two types of sign-off's: front-end sign-off and back-end sign-off. After back-end sign-off, the chip goes to fabrication. After listing out all the features in the specification, the verification engineer will write coverage for those features to identify bugs, and send back the RTL design to the designer. Bugs, or defects, can include issues like missing features, errors in design, etc. When the coverage reaches a maximum percentage then the verification team will sign it off. By using a methodology like UVM, OVM, or VMM, the verification team develops a reusable environment. Nowadays, UVM is more popular than others.
This page is a comparison of electronic design automation (EDA) software which is used today to design the near totality of electronic devices. Modern electronic devices are too complex to be designed without the help of a computer. Electronic devices may consist of integrated circuits (ICs), printed circuit boards (PCBs), field-programmable gate arrays (FPGAs) or a combination of them. Integrated circuits may consist of a combination of digital and analog circuits. These circuits can contain a combination of transistors, resistors, capacitors or specialized components such as analog neural networks, antennas or fuses.
The Point Cloud Library (PCL) is an open-source library of algorithms for point cloud processing tasks and 3D geometry processing, such as occur in three-dimensional computer vision. The library contains algorithms for filtering, feature estimation, surface reconstruction, 3D registration, model fitting, object recognition, and segmentation. Each module is implemented as a smaller library that can be compiled separately. PCL has its own data format for storing point clouds - PCD, but also allows datasets to be loaded and saved in many other formats. It is written in C++ and released under the BSD license.
LAVIS is a software tool created by the TOOL Corporation, Japan. LAVIS is a "layout visualisation platform". It supports a variety of formats such as GDSII, OASIS and LEF/DEF and can be used as a platform for common IC processes.
* Clein, Dan. (2000). CMOS IC Layout. Newnes. ISBN 0-7506-7194-7
* [GDS78] Calma. (1978). GDS II Graphic Design System User's Operating Manual, First Edition 1978. Online at http://www.bitsavers.org/pdf/calma/GDS_II_Users_Operating_Manual_Nov78.pdf Retrieved Apr 21, 2020.