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Max. Probability Detected - % Column

Description
This column is listed under the Max. Probability Detected label in the Detection Order Table section of the Detection Order Report. Each entry in this column contains the probability-weighted percentage of previously-undetected used functions that are detected (called into suspicion) when a detection test fails. The Test limits in this column are order-specific; if the detection tests were to be performed in a different order, then each test may have a different Test limit in this column (since some of that test's coverage may have been proven good by previous tests in the detection sequence).
 
This column differs from the  Min. Probability Detected % column in that it accounts for failures that can cause the corresponding test to fail, yet which cannot be proven good when the test passes (this includes failures to functions that are categorized as interference).
 
Calculation
This Test limit can be calculated by summing the partial failure probabilities for all used functions in the specified Diagnostic Scope that have not been detected by a previous test in the Detection Sequence and which can be detected when the corresponding test fails (all preceding tests in the detection order having already passed).
 
When fault detection is calculated across the entire design (i.e., the Diagnostic Scope is set to <Entire Design>), this metric can be calculated using the following equation:
where
N
=
the total number of used functions (for the current hierarchical expansion)
Xi
=
1 if the ith function is detected (either partially or fully) as a result of detection test x failing; 0 otherwise
NDi
=
1 if the ith function has not been detected (either partially or fully) by a previous test; 0 otherwise
Pfpi
=
the partial failure probability associated with the portion of the ith function that is partially or fully detected as a result of detection test x having failed (and which has not been detected by a previous test)
 
When fault detection is calculated with the Diagnostic Scope restricted to a specific Operating Mode, then this metric is calculated as follows:
where
N
=
the total number of used functions (for the current hierarchical expansion)
Xi
=
1 if the ith function is detected (either partially or fully) as a result of detection test x failing; 0 otherwise
NDi
=
1 if the ith function has not been detected (either partially or fully) by a previous test; 0 otherwise
Pfpi
=
the partial failure probability associated with the portion of the ith function that is partially or fully detected as a result of detection test x having failed (and which has not been detected by a previous test)
Si
=
1 if the ith function is in the Operating Mode specified by the Diagnostic Scope or if the Scale Statistics to Scope option has been disabled; 0 otherwise