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Max. Probability Detected - Cum % 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 used functions that can be detected by the tests in the detection order up to and including the current test. 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 additional functions may have been detected by previous tests in the detection sequence).
 
Calculation
This Test limit can be calculated by summing the partial failure probabilities for all used functions in the specified Diagnostic Scope that can be detected by the tests up to and including the current test.
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 can be detected (either partially or fully) by one of the first x tests in the detection order; 0 otherwise
Pfpi
=
the partial failure probability associated with the portion of the ith function that can be detected by one of the first x detection tests
 
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) by one of the first x tests in the detection order; 0 otherwise
Pfpi
=
the partial failure probability associated with the portion of the ith function that can be detected by one of the first x detection tests
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
 
Alternatively, this metric can be calculated by summing the Test limits in the  Max. Probability Detected % column for all tests up to and including the current test:
where
MinProbDeti
=
the Test limit in the  Max. Probability Detected % column corresponding to ith test in the detection order.
x
=
the position of the current test in the detection order