SpyGlass
®
DFT
Rules Reference Guide
Version L-2016.06, June 2016
Copyright Notice and Proprietary Information
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Contents
Preface........................................................................................25
About This Book.................................................................................... 25
Contents of This Book ........................................................................... 26
Typographical Conventions ................................................................... 27
Understanding the SpyGlass DFT Product ...................................29
Key Concepts ........................................................................................ 30
RTL Design for Test..............................................................................31
SpyGlass DFT Design Constraints...........................................................39
Operating Modes .................................................................................48
Types of Flip-Flops...............................................................................53
Types of Latches..................................................................................55
Identifying Clock Gating Cells................................................................60
Types of Faults....................................................................................72
Support for Multi-Bit Flip-Flop Cells........................................................79
Support For Clock Shaper with Scannable Flip- Flops................................80
Using AutoFix and Selective AutoFix.......................................................82
Identifying Test Points To Reduce Random Resistance ...............................84
Design Impact....................................................................................... 86
Scannability........................................................................................86
Improvements to Fault and Test Coverage...............................................87
Detecting Structures Leading to Non-Robust Tests....................................95
Suggested SpyGlass DFT Operation....................................................... 96
Use of Design Constraints.....................................................................97
Making the RTL scan ready ...................................................................99
Comply with SpyGlass DFT Best Practices .............................................102
Adding Test Points .............................................................................103
Identifying Testclocks.........................................................................104
Working with Scan Chains...................................................................105
Checking Block-level Test Requirements................................................108
Making the RTL Ready for Atspeed Test.................................................108
