Reuse Test Patterns for Structurally Similar Circuits

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current test generation processes for complex integrated circuits are inefficient due to the lack of utilization of structural similarity between circuits, leading to repeated and time-consuming test pattern generation.

Innovation Solution

A method that analyzes structural similarity between two circuit designs, modifies existing test patterns by reusing bit values associated with structurally similar parts, and performs fault simulation to generate optimized test patterns for the second circuit design.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional test generation processes are used for each circuit design independently, then complete fault coverage can be achieved, but test generation time increases significantly

Engineering Contradiction:
Improvefault coverageVSAvoidtest generation time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent creates a mapping between structurally similar circuits by copying test patterns from a first circuit to a second circuit. The test pattern generation system identifies structural similarities between circuits and uses this information to copy applicable test patterns, thereby avoiding redundant test generation while maintaining fault coverage for the second circuit.

Inventive Principle:
Principle #26Copying

Solution Approach 2:

The patent transforms test patterns by modifying parameters such as bit values and pattern structures based on the structural differences between circuits. The system adjusts test pattern parameters (e.g., bit assignments, pattern sequences) to accommodate variations in the second circuit while retaining the core testing effectiveness from the first circuit.

Inventive Principle:
Principle #35Parameter changes

2Productivity

If structural similarity between circuits is not utilized, then test generation is straightforward, but runtime increases due to repeated analysis

Engineering Contradiction:
Improvetest generation speedVSAvoidanalysis runtime
Core Design Contradiction:
ProductivityVSLoss of time

Solution Approach 1:

The patent performs preliminary analysis of structural similarity between circuits before generating test patterns. By pre-identifying structural correspondences and creating mappings between circuits, the system prepares reusability information in advance, enabling rapid test pattern generation without repeating the entire analysis process for each circuit.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent creates a universal test pattern generation approach that handles multiple structurally similar circuits through a single framework. The system establishes a universal mapping mechanism that can apply test patterns across different circuits with structural similarities, making the test generation process multi-functional and reusable rather than circuit-specific.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Stability of the object's composition

If all gate instances are ordered using signature values, then minimal change in gate order is guaranteed, but some structure differences are not captured

Engineering Contradiction:
Improvegate instance order stabilityVSAvoidstructure difference detection
Core Design Contradiction:
Stability of the object's compositionVSDifficulty of detecting and measuring

Solution Approach 1:

The patent applies local quality analysis by examining specific regions or modules within circuits rather than treating the entire circuit uniformly. The system identifies local structural similarities and differences in specific gate instances or sub-circuits, allowing for more precise detection of structure differences while maintaining stability in the overall gate ordering through localized comparisons.

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP4305541B1Test generation for structurally similar circuits
Publication Date: 2025.05.28 SIEMENS INDUSTRY SOFTWARE INC
  • EP4305541B1 patent drawingFigure 1
  • EP4305541B1 patent drawingFigure 2
  • EP4305541B1 patent drawingFigure 3

AI summary

A first circuit design and a second circuit design are analyzed to determine part of the second circuit design structurally similar to part of the first circuit design. A first set of test patterns for the first circuit design is modified to generate a second set of test patterns for the second circuit design by reusing values of bits in the first set of test patterns associated with the part of the first circuit design as values of bits in the second set of test patterns associated with the part of the second circuit design. Fault simulation is performed on the second circuit design using the second set of test patterns to determine a subset of faults undetectable by the second set of test patterns. Test pattern generation is performed for the subset of faults to generate a third set of test patterns for the second circuit design.