EDA database

Last updated

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.

Contents

In examining EDA design databases, it is useful to look at EDA tool architecture, to determine which parts are to be considered part of the design database, and which parts are the application levels. In addition to the database itself, many other components are needed for a useful EDA application. Associated with a database are one or more language systems (which, although not directly part of the database, are used by EDA applications such as parameterized cells and user scripts). On top of the database are built the algorithmic engines within the tool (such as timing, placement, routing, or simulation engines ), and the highest level represents the applications built from these component blocks, such as floorplanning. The scope of the design database includes the actual design, library information, technology information, and the set of translators to and from external formats such as Verilog and GDSII.

Mature design databases

Many instances of mature design databases exist in the EDA industry, both as a basis for commercial EDA tools as well as proprietary EDA tools developed by the CAD groups of major electronics companies. IBM, Hewlett-Packard, SDA Systems and ECAD (now Cadence Design Systems), High Level Design Systems, and many other companies developed EDA specific databases over the last 20 years, and these continue to be the basis of IC-design systems today. Many of these systems took ideas from university research and successfully productized them. Most of the mature design databases have evolved to the point where they can represent netlist data, layout data, and the ties between the two. They are hierarchical to allow for reuse and smaller designs. They can support styles of layout from digital through pure analog and many styles of mixed-signal design.

Current design databases

The OpenAccess design database

Given the importance of a common design database in the EDA industry, the OpenAccess Coalition has been formed to develop, deploy, and support an open-sourced EDA design database with shared control. The data model presented in the OA DB provides a unified model that currently extends from structural RTL through GDSII-level mask data, and now into the reticle and wafer space. It provides a rich enough capability to support digital, analog, and mixed-signal design data. It provides technology data that can express foundry process design rules through at least 20 nm, contains the definitions of the layers and purposes used in the design, definitions of VIAs and routing rules, definitions of operating points used for analysis, and so on. OA makes extensive use of IC-specific data compression techniques to reduce the memory footprint, to address the size, capacity, and performance problems of previous DBs. Despite what its name could imply, this file format has no publicly accessible implementation or specification. Those are exclusive to the members of the OpenAccess Coalition.

Synopsys Milkyway

The Milkyway database was originally developed by Avanti Corporation, which has since been acquired by Synopsys. It was first released in 1997. Milkyway is the database underlying most of Synopsys' physical design tools:

Milkyway stores topological, parasitic and timing data. Having been used to design thousands of chips, Milkyway is very stable and production worthy. Milkyway is known to be written in C. Its internal implementation is not available outside Synopsys, so no comments may be made about the implementation.

MDX C-API

At the request of large customers such as Texas Instruments, Avanti released the MDX C-API in 1998. This enables the customers' CAD developers to create plugins that add custom functionality to Milkyway tools (chiefly Astro).

MDX allows fairly complete access to topological data in Milkyway, but does not support timing or RC parasitic data.

MAP-in Program

In early 2003, Synopsys (which acquired Avanti) opened Milkyway through the Milkyway Access Program (MAP-In). Any EDA company may become a MAP-in member for free (Synopsys customers must use MDX). Members are provided the means to interface their software to Milkyway using C, Tcl, or Scheme. The Scheme interface is deprecated in favor of TCL. IC Compiler supports only TCL.

The MAP-in C-API enables a non-Synopsys application to read and write Milkyway databases. Unlike MDX, MAP-in does not permit the creation of a plugin that can be used from within Synopsys Milkyway tools. MAP-in does not support access to timing or RC parasitic data. MAP-in also lacks direct support of certain geometric objects.

MAP-in includes Milkyway Development Environment (MDE). MDE is a GUI application used to develop TCL and Scheme interfaces and diagnose problems. Its major features include:

  • Graphical editor for viewing and editing Milkyway databases
  • TCL command interpreter
  • Scheme command interpreter
  • Translators to read and write popular formats like Verilog, LEF, DEF and GDSII

Falcon from Mentor

Another significant design database is Falcon, from Mentor Graphics. This database was one of the first in the industry written in C++. Like Milkyway is for Synopsys, Falcon seems to be a stable and mature platform for Mentor’s IC products. Again, the implementation is not publicly available, so little can be said about its features or performance relative to other industry standards.

Magma's database

Magma Design Automation’s database is not just a disk format with an API, but is an entire system built around their DB as a central data structure. Again, since the details of the system are not publicly available, a direct comparison of features or performance is not possible. Looking at the capabilities of the Magma tools would indicate that this DB has a similar functionality to OpenAccess, and may be capable of representing behavioral (synthesis input) information.

Major features of an EDA specific database

An EDA specific database is expected to provide many basic constructs and services. Here is a brief and incomplete list of what is needed:

Related Research Articles

In computer engineering, a hardware description language (HDL) is a specialized computer language used to describe the structure and behavior of electronic circuits, and most commonly, digital logic circuits.

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).

<span class="mw-page-title-main">Synopsys</span> American software company

Synopsys is an American electronic design automation (EDA) company headquartered in Sunnyvale, California, that focuses on silicon design and verification, silicon intellectual property and software security and quality. Synopsys supplies tools and services to the semiconductor design and manufacturing industry. Products include tools for logic synthesis and physical design of integrated circuits, simulators for development, and debugging environments that assist in the design of the logic for chips and computer systems. As of 2023, the company is a component of both the Nasdaq-100 and S&P 500 indices.

In software engineering, the terms frontend and backend refer to the separation of concerns between the presentation layer (frontend), and the data access layer (backend) of a piece of software, or the physical infrastructure or hardware. In the client–server model, the client is usually considered the frontend and the server is usually considered the backend, even when some presentation work is actually done on the server itself.

<span class="mw-page-title-main">Accellera</span>

Accellera Systems Initiative (Accellera) is a standards organization that supports a mix of user and vendor standards and open interfaces development in the area of electronic design automation (EDA) and integrated circuit (IC) design and manufacturing. It is less constrained than the Institute of Electrical and Electronics Engineers (IEEE) and is therefore the starting place for many standards. Once mature and adopted by the broader community, the standards are usually transferred to the IEEE.

<span class="mw-page-title-main">GDSII</span> Database file format for data exchange of integrated circuit layout artwork

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. It is a binary file format representing planar geometric shapes, text labels, and other information about the layout in hierarchical form. 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.

OpenAccess is a proprietary API controlled by the OpenAccess Coalition that aims to facilitate Interoperability of electronic design automation software among the members of that coalition.

VLSI Technology, Inc., was an American company that designed and manufactured custom and semi-custom integrated circuits (ICs). The company was based in Silicon Valley, with headquarters at 1109 McKay Drive in San Jose. Along with LSI Logic, VLSI Technology defined the leading edge of the application-specific integrated circuit (ASIC) business, which accelerated the push of powerful embedded systems into affordable products.

<span class="mw-page-title-main">Standard cell</span>

In semiconductor design, standard-cell methodology is a method of designing application-specific integrated circuits (ASICs) with mostly digital-logic features. Standard-cell methodology is an example of design abstraction, whereby a low-level very-large-scale integration (VLSI) layout is encapsulated into an abstract logic representation.

<span class="mw-page-title-main">SystemVerilog</span> Hardware description and hardware verification language

SystemVerilog, standardized as IEEE 1800, is a hardware description and hardware verification language used to model, design, simulate, test and implement electronic systems. SystemVerilog is based on Verilog and some extensions, and since 2008, Verilog is now part of the same IEEE standard. It is commonly used in the semiconductor and electronic design industry as an evolution of Verilog.

<span class="mw-page-title-main">Integrated circuit design</span> Engineering process for electronic hardware

Integrated circuit design, or IC design, is a sub-field of electronics engineering, encompassing the particular logic and circuit design techniques required to design integrated circuits, or ICs. ICs consist of miniaturized electronic components built into an electrical network on a monolithic semiconductor substrate by photolithography.

Design flows are the explicit combination of electronic design automation tools to accomplish the design of an integrated circuit. Moore's law has driven the entire IC implementation RTL to GDSII design flows from one which uses primarily stand-alone synthesis, placement, and routing algorithms to an integrated construction and analysis flows for design closure. The challenges of rising interconnect delay led to a new way of thinking about and integrating design closure tools.

The Timing closure in VLSI design and electronics engineering is the process by which a logic design of a clocked synchronous circuit consisting of primitive elements such as combinatorial logic gates and sequential logic gates is modified to meet its timing requirements. Unlike in a computer program where there is no explicit delay to perform a calculation, logic circuits have intrinsic and well defined delays to propagate inputs to outputs.

<span class="mw-page-title-main">Cadence Design Systems</span> American multinational computational software company

Cadence Design Systems, Inc., headquartered in San Jose, California, is an American multinational computational software company, founded in 1988 by the merger of SDA Systems and ECAD, Inc. The company produces software, hardware, and silicon structures for designing integrated circuits, systems on chips (SoCs), and printed circuit boards.

IP-XACT is an XML format that defines and describes individual, re-usable electronic circuit designs to facilitate their use in creating integrated circuits. IP-XACT was created by the SPIRIT Consortium as a standard to enable automated configuration and integration through tools.

The Design Automation Standards Committee (DASC) is a subgroup of interested individuals members of the Institute of Electrical and Electronics Engineers (IEEE) Computer Society and Standards Association. It oversees IEEE Standards that are related to computer-aided design. It is part of the IEEE Computer Society.

High-level synthesis (HLS), sometimes referred to as C synthesis, electronic system-level (ESL) synthesis, algorithmic synthesis, or behavioral synthesis, is an automated design process that takes an abstract behavioral specification of a digital system and finds a register-transfer level structure that realizes the given behavior.

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.

<span class="mw-page-title-main">EVE/ZeBu</span> Provider of hardware-assisted verification tools

EVE/ZeBu is a provider of hardware-assisted verification tools for functional verification of Application-specific integrated circuits (ASICs) and system on chip (SOC) designs and for validation of embedded software ahead of implementation in silicon. EVE's hardware acceleration and hardware emulation products work in conjunction with Verilog, SystemVerilog, and VHDL-based simulators from Synopsys, Cadence Design Systems and Mentor Graphics. EVE's flagship product is ZeBu.

Tcl is a high-level, general-purpose, interpreted, dynamic programming language. It was designed with the goal of being very simple but powerful. Tcl casts everything into the mold of a command, even programming constructs like variable assignment and procedure definition. Tcl supports multiple programming paradigms, including object-oriented, imperative, functional, and procedural styles.

References