LEF/DEF Language Reference - ISPD

1 LEF/DEF Language ReferenceProduct Version November 2009 1990-2008 Cadence Design Systems, Inc. All rights reserved. Printed in the United States of Design Systems, Inc., 555 River Oaks Parkway, San Jose, CA 95134, USAT rademarks: Trademarks and service marks of Cadence Design Systems, Inc. (Cadence) contained in this document are attributed to Cadence with the appropriate symbol. For queries regarding Cadence s trademarks, contact the corporate legal department at the address shown above or call SystemC, Open SystemC Initiative, OSCI, SystemC, and SystemC Initiative are trademarks or registered trademarks of Open SystemC Initiative, Inc. in the United States and other countries and are used with other trademarks are the property of their respective Print Permission: This publication is protected by copyright and any unauthorized use of this publication may violate copyright, trademark, and other laws.

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3 The information contained herein is the proprietary and confidential information of Cadence or its licensors, and is supplied subject to, and may be used only by Cadence s customer in accordance with, a written agreement between Cadence and its customer. Except as may be explicitly set forth in such agreement, Cadence does not make, and expressly disclaims, any representations or warranties as to the completeness, accuracy or usefulness of the information contained in this document. Cadence does not warrant that use of such information will not infringe any third party rights, nor does Cadence assume any liability for damages or costs of any kind that may result from use of such Rights: Use, duplication, or disclosure by the Government is subject to restrictions as set forth in and et seq. or its successor. LEF/DEF Language ReferenceNovember 20093 Product Version .. 7 What s New.

4 7 Typographic and Syntax Conventions .. 7 Character Information .. 81 LEF Syntax .. 11 About Library Exchange Format Files .. 12 General Rules .. 12 Name Escaping Semantics for LEF/DEF Files .. 12 Managing LEF Files .. 13 Order of LEF Statements .. 14 LEF Statement Definitions .. 14 Bus Bit Characters .. 14 Clearance Measure .. 15 Divider Character .. 15 Extensions .. 15 Layer (Cut) .. 16 Layer (Implant) .. 74 Layer (Masterslice or Overlap) .. 76 Layer (Routing) .. 79 Macro .. 172 Manufacturing Grid .. 202 Maximum Via Stack .. 202 Nondefault Rule .. 203 Property Definitions .. 207 Site .. 209 Units .. 211 Use Min Spacing .. 214 Version .. 214 Via .. 215 ContentsLEF/DEF Language ReferenceNovember 20094 Product Version Rule .. 220 Via Rule Generate .. 2212 ALIAS Statements .. 227 ALIAS Statements .. 227 ALIAS Definition .. 228 ALIAS Examples.

5 228 ALIAS Expansion .. 2293 Working with LEF.. 231 Incremental LEF .. 231 Error Checking .. 232 Message Facility .. 233 Error-Checking Facility .. 2354 DEF Syntax.. 237 About Design Exchange Format Files .. 238 General Rules .. 239 Name Escaping Semantics for LEF/DEF Files .. 239 Order of DEF Statements .. 241 DEF Statement Definitions .. 242 Blockages .. 242 Bus Bit Characters .. 246 Components .. 246 Design .. 251 Die Area .. 251 Divider Character .. 252 Extensions .. 252 Fills .. 252 GCell Grid .. 254 Groups .. 256 LEF/DEF Language ReferenceNovember 20095 Product Version .. 256 Nets .. 257 Nondefault Rules .. 268 Pins .. 271 Pin Properties .. 286 Property Definitions .. 287 Regions .. 288 Rows .. 289 Scan Chains .. 290 Slots .. 296 Special Nets .. 298 Styles .. 310Te c h n o l o g y .. 322 Tracks .. 322 Units .. 323 Version .. 324 Vias.

6 325 AExamples .. 333 LEF .. 333 DEF .. 344 Scan Chain Synthesis Example .. 349 BOptimizing LEF Technology for Place and Route.. 351 Overview .. 351 Guidelines for Routing Pitch .. 352 Guidelines for Wide Metal Spacing .. 354 Guidelines for Wire Extension at Vias .. 355 Guidelines for Default Vias .. 357 Guidelines for Stack Vias (MAR Vias) and Samenet Spacing .. 359 Example of an Optimized LEF Technology File .. 363 LEF/DEF Language ReferenceNovember 20096 Product Version and Fixing Process Antenna Violations.. 369 Overview .. 370 What Are Process Antennas? .. 371 What Is the Process Antenna Effect (PAE)? .. 372 What Is the Antenna Ratio? .. 373 What Can Be Done to Improve the Antenna Ratio? .. 373 Using Process Antenna Keywords in the LEF and DEF Files .. 374 Calculating Antenna Ratios .. 375 Calculating the Antenna Area .. 375 Calculating a PAR .. 376 Calculating a CAR.

7 381 Calculating Ratios for a Cut Layer .. 389 Checking for Antenna Violations .. 392 Area Ratio Check .. 393 Side Area Ratio Check .. 393 Cumulative Area Ratio Check .. 394 Cumulative Side Area Ratio Check .. 395 Cut Layer Process Antenna Model Examples .. 395 Routing Layer Process Antenna Model Examples .. 396 Example Using the Antenna Keywords .. 402 Using Antenna Diode Cells .. 403 Changing the Routing .. 404 Inserting Antenna Diode Cells .. 404 Using DiffUseOnly .. 404 Calculations for Hierarchical Designs .. 405 LEF and DEF Keywords for Hierarchical Designs .. 406 Design Example .. 406To p - D o w n H i e r a r c h i c a l D e s i g n E x a m p l e .. 409 Index.. 411 LEF/DEF Language ReferenceNovember 20097 Product Version manual is a Language Reference for users of the Cadence Library Exchange Format (LEF) and Design Exchange Format (DEF) integrated circuit (IC) description languages.

8 LEF defines the elements of an IC process technology and associated library of cell models. DEF defines the elements of an IC design relevant to physical layout, including the netlist and design constraints. LEF and DEF inputs are in ASCII manual assumes that you are familiar with the development and design of integrated circuits. This preface provides the following information: What s New on page 7 Typographic and Syntax Conventions on page 7 Character Information on page 8 What s NewFor information on what is new or changed in LEF and DEF for version see What s New in LEF/DEF . Typographic and Syntax ConventionsThis list describes the conventions used in this in monospace type indicate keywords that you must enter literally. These keywords represent Language in italics indicate user-defined information for which you must substitute a name or a object name with the identifier objRegExpr represents a regular expression for the object name.

9 LEF/DEF Language ReferencePrefaceNovember 20098 Product Version a point in the design. This value corresponds to a coordinate pair, such as x y. You must enclose a point within parentheses, with space between the parentheses and the coordinates. For example, RECT ( 1000 2000 ) ( 1500 400 ).|Vertical bars separate possible choices for a single argument. They take precedence over any other character. [ ]Brackets denote optional arguments. When used with vertical bars, they enclose a list of choices from which you can choose one.{ } ..Braces followed by three dots indicate that you must specify the argument at least once, but you can specify it multiple times.{ }Braces used with vertical bars enclose a list of choices from which you must choose dots indicate that you can repeat the previous argument. If they are used with brackets, you can specify zero or more arguments. If they are used with braces, you must specify at least one argument, but you can specify more.

10 ,..A comma and three dots together indicate that if you specify more than one argument, you must separate those arguments with commas." "Quotation marks enclose string values. Write quotation marks within a string as \". Write a backslash within a string as \\.Any characters not included in the list above are required by the Language and must be entered InformationLEF and DEF support the following characters:! < and > $ . (period) LEF/DEF Language ReferencePrefaceNovember 20099 Product Version reserves the following characters for special functions: LEF and DEF names cannot contain the following ASCII characters:Note: LEF and DEF names also cannot contain the ASCII character used by the place-and-route tool for comments. For example, if the tool uses the pound sign (#) for comments, it cannot be used in a LEF or DEF and DEF interpret the following characters as regular expressions.