Partitioned scan chain diagnostics using multiple bypass structures and injection points

摘要

A method and apparatus are provided for isolating a defect in a scan chain comprising a plurality of components of an integrated circuit. A plurality of injection points may be positioned along the scan chain. Each injection point may be configured to introduce binary test data. A plurality of bypass structures may each be configured to selectively direct a flow of the binary test data to generate a plurality of partitioned scan paths. Test logic may be configured to execute a plurality of tests using the plurality of partitioned scan paths and to combine results of the plurality of tests to isolate a faulty component of the plurality of components.

主权项

1. A method of determining a faulty component in an integrated circuit, the method comprising:
sending, from a processor to a plurality of bypass structures of a scan chain, configuration signals to generate first and second partitioned scan chains of the scan chain, the scan chain including the plurality of bypass structures, multiple injection point components, and a plurality of components of an integrated circuit, wherein at least one injection point component of the multiple injection point components includes a corresponding output that is coupled to two bypass structures of the plurality of bypass structures; providing, by the processor, an input signal to an input of the at least one injection point component to set a value at an output of the at least one injection point component; determining, at the processor, test results associated with at least one of the first and second partitioned scan chains, the test results based on the value; and identifying, by the processor, a first failed component of the plurality of components responsive to a failure determined based on the test results.