Mentor v8.6_4 manual ∙ failurefilename, ∙ -Lastpatternnumber patternname, ∙ -Outputreportfilename

Command Dictionary Diagnose Failures

The primary use for this command is for diagnostics.

!

Caution

When using ATE failure data, the ATE must finish collecting fail data on the complete pattern boundary. This is because the Diagnose Failures command assumes that any cells or primary outputs not included in the failing patterns file passed the testing. If the tester did not finish, the diagnosis summary report may yield inconclusive or unreliable results.

If you suspect that a scan chain defect is causing a scan cell to remain at a constant state, use the -Chain switch. The diagnosis then identifies the scan cell closest to the scan-in pin that will not achieve both a 0 and 1 state. The analysis assumes that the scan cells closer to the scan-out pin will be able to capture both a 0 and 1 value and that the tool will successfully observe them because the state does not have to propagate through the defective scan cell. The diagnosis reports the scan cell that is most likely to contain the defect and gives the name and ID number of its master element. If no scan chains appear to have a fixed value scan cell, the command reports a message to that effect.

Arguments

∙failure_filename

A required string that specifies the name of the file, generated by an ATE tester, that contains the failing pattern identifications.

∙-Lastpattern_number pattern_name

An optional switch that specifies the line number or name of the pattern identifier in the failure_filename at which the tester truncated the test. For FastScan, pattern_number is an integer pair and pattern_name is a string generated by using the -tag tag_name switch with the Save Patterns command (which specifies a prefix for all pattern names). For example, pattern_name = tag_name_1, tag_name_2, etc.

If you do not specify the -Last switch, the tool assumes that failure_filename includes all the failing patterns.

∙-Outputreport_filename

An optional switch and string pair that specifies the name of the file to which you want to write the diagnostic report.

FastScan and FlexTest Reference Manual, V8.6_4 2-221