Synopsys, Inc.

Denis Martin

Harbinder Singh

Amit Gopal M Purohit

Paras Chhabra

Rohit Kapur

Thomas W Williams

Dhiraj Goswami

Robert L Walker

Ajay Khoche

Sorin Ioan Popa

Srinivas Ajjarapu

A first scan pattern may be received to test a first circuit block in an integrated circuit (IC) design and a second scan pattern may be received to test a second circuit block in the IC design. A first length of the first scan pattern may be different from a second length of the second scan pattern. The first scan pattern, the second scan pattern, or both the first scan pattern and the second scan pattern may be modified to make lengths of the first scan pattern and the second scan pattern equal.

Modifying scan patterns to enable broadcasting a scan enable signal to multiple circuit blocks

A method includes identifying state holding pipeline stages in a pipeline path of a design for test (DFT) of an integrated circuit design, splitting each pattern of a plurality of patterns into a first part and a second part, reformatting the plurality of patterns to generate another plurality of patterns such that the first part and the second part of each pattern of the plurality patterns are included in different patterns of the another plurality of patterns. The length of the first part is a function of a number of the identified pipeline stages.

Reformatting scan patterns in presence of hold type pipelines

According to the present invention, during scan conversion, non-scan memory cells of a circuit design are replaced with scan cells to form a scan chain. The scan chain is transformed by the test synthesis tool of the present invention into dynamic scan chains with the addition of reconfiguration circuitry. The reconfiguration circuitry partitions the scan chain into multiple segments and enables each segment to be selectively &ldquo;bypassed&rdquo; (or deactivated) during test application. Shorter test patterns that are only pertinent to one or more segments are necessary, resulting in a reduction in overall test data volume and test application time. The present invention also provides a modified ATPG technique for generating test patterns for the dynamic scan chains.

Dynamic scan chains and test pattern generation methodologies therefor

A computer implemented process and system for electronic design automation (EDA) using groups of multiple cells having loop-back connections for modeling port electrical characteristics. Multi-bit cells have multiple gates of the same function implemented within a same cell. Multi-bit components have multiple multi-bit cells implemented within a same component. Scannable multi-bit cells and components are similar to multi-bit cells and components but contain scannable sequential elements with scan chains installed. Multi-bit cells may or may not have each sequential cells' input and each sequential cells' output available externally. The scannable sequential elements of a multi-bit component are ordered into a predefined scan chain which is defined by the library containing the multi-bit component or multi-bit cell. During scan replacement processes of the EDA compile process, multi-bit cells and components of the netlist are replaced with scannable multi-bit cells and components. Also, during optimization, multi-bit cells and components undergo equivalence replacement to meet specified constraints (e.g., area, performance, etc.). To model the electrical characteristics of the port during certain optimizations, loopback connections are applied to the multi-bit components from the scan out port to the scan in port of the multi-bit cell or component, therefore, one loopback connection spans multiple sequential cells within the multi-bit cell or component. During certain optimizations, loopback connections are applied to multiple sequential cells that are coupled together but do not necessarily reside in a multi-bit cell or component. By spanning multiple sequential cells, circuit degeneration is reduced thereby providing better circuit optimizations for netlists having scan circuitry.

Electronic design automation system and methods utilizing groups of multiple cells having loop-back connections for modeling port electrical characteristics

A method of and system for inserting test points within an integrated circuit design. According to the present invention, test points are inserted early in the electronic design process and prior to logic synthesis such that the problem of design constraint violation can be avoided. One embodiment of the present invention includes the computer implemented steps of receiving an unmapped netlist of an integrated circuit design, and receiving from an external source, data that indicates the location and the desired functionality of the test point to be inserted. Thereafter, the present invention inserts a generic test point circuit at the indicated location and generates a modified unmapped netlist. Subsequently, the present invention performs a logic synthesis process on the modified unmapped netlist where the generic test point circuit is degenerated into an actual test point circuit for performing the desired functionality. The actual test point circuit may also be merged with other circuitries of the integrated circuit to produce a more efficient design.

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Palo Alto, CA, United States of America

Denis Martin