Synopsys, Inc.

Parthajit Bhattacharya

Rohit Kapur

Jyotirmoy Saikia

Anshuman Chandra

Subramanian Chebiyam

Subhadip Kundu

Ramakrishnan Balasubramanian

Rajesh Uppuluri

Ashwin Kumar

Sunil Reddy Tiyyagura

Sushovan Podder

Information is received describing test response signals generated by scan cells of an integrated circuit and physical shift failures representing mismatches between the test response signals and expected test response signals of the integrated circuit. The test response signals are mapped to a subset of the scan cells associated with the physical shift failures. Fault simulation is performed for the mapped subset of the scan cells to identify physical faults located within the integrated circuit causing the physical shift failures.

Mapping physical shift failures to scan cells for detecting physical faults in integrated circuits

A method for masking scan chains in a test circuit of an integrated circuit is disclosed. The test circuit includes multiple mask banks. Different mask patterns are stored in each of the mask banks. A first mask bank of the multiple mask banks is selected and the mask pattern stored in the selected first mask bank is used for masking the output of the scan chains of the test circuit during a first portion of a test cycle. A second mask bank of the multiple mask banks is selected and the ask pattern stored in the selected second mask bank is used for masking the output of the scan chains of the test circuit during a second portion of the test cycle.

Handling of undesirable distribution of unknown values in testing of circuit using automated test equipment

A disclosed configuration is for identifying at least one failure indicating scan test cell of a circuit-under-test, CUT, the CUT having a plurality of scan test cells, is provided. The configuration comprises generating a plurality of error signatures by means of a compactor of the CUT, wherein each of the error signatures of the plurality of error signatures consist of a respective sequence of bits comprising at least one failure indicating bit, assigning each error signature to at least a first, a second and a third signature type according to a total number of failure indicating bits of the respective error signature and mapping at least a predefined minimum number of error signatures to respective scan test cells of the plurality of scan test cells. For each error signature, a priority of the mapping is determined by the signature type the respective error signature has been assigned to.

Identifying failure indicating scan test cells of a circuit-under-test

Operating a scan chain of a test circuit of an integrated circuit to have either a single fanout or multiple fanout to a compressor. The test circuit receives a fanout control signal for configuring the fanout of the scan chain. If the fanout control signal indicates configuring of the scan chain with a single fanout, the output of the scan chain is sent to one input of a compressor. If the fanout control signal indicates configuring of the scan chain with multiple fanout, the output of the scan chain is sent to multiple inputs of the compressor.

Scheme for masking output of scan chains in test circuit

A method for reordering a test pattern set for testing an integrated circuit is disclosed. A productivity index is computed for each test pattern in a test pattern set. The productivity index of a first test pattern and the productivity index of a second test pattern are compared. If the productivity index of the second test pattern is larger than the productivity index of the first test pattern, the location of the first test pattern and the second test pattern are swapped.

Reordering or removal of test patterns for detecting faults in integrated circuit

A method for localizing at least one scan flop associated with a fault in an integrated circuit. A first test pattern, including a first scan-in data and first control data, is generated. Based on the first control data of the first test pattern, a first fault data is generated by applying the first scan-in data of the first test pattern to scan flops in a test circuit of the integrated circuit. If the first fault data indicates that a fault may be present in the integrated circuit, a second test pattern, including a second scan-in data and a second control data is generated.

Localizing fault flop in circuit by using modified test pattern

Systems and methods provide acceleration of automatic test pattern generation in a multi-core computing environment via multi-level parameter value optimization for a parameter set with speculative scheduling. The methods described herein use multi-core based parallel runs to parallelize sequential execution, speculative software execution to explore possible parameter sets, and terminate/prune runs when the optimum parameter value is found at a previous level. The present invention evaluates the design prior to the implementation of the compression IP so that it can define the configuration of DFT and ATPG to maximize the results of compression as measured by test data volume and test application time.

Accelerating automatic test pattern generation in a multi-core computing environment via speculatively scheduled sequential multi-level parameter value optimization

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Bengaluru, India

Parthajit Bhattacharya