Command Dictionary

Analyze Observe

 

 

Analyze Observe

Tools Supported: FastScan

Scope: Atpg, Fault, and Good modes

Usage

ANAlyze OBserve

Description

Calculates observability coverage.

The Analyze Observe command identifies points that were inadequately observed during application of the selected number of random patterns. FastScan calculates observability test coverage, giving the percentage of adequately-observed pins.

You can specify the minimum number of observations (threshold) necessary for adequate observation of a point with the Set Observe Threshold command. The tool identifies the most difficult to observe fault points, those which fail the threshold number, as inadequately observed.

After issuing the Analyze Observe command, you can display detailed results of the analysis using the Report Observe Data command. This information helps you identify circuit observe points that can increase observability for points that had low observability. You can then evaluate the effect of these observe points by using the Add Observe Points command and then reissuing the Analyze Observe command.

You use this command primarily for simulating Built-In Self Test (BIST) circuitry.

Examples

The following example calculates observability test coverage for pins which fail to achieve a minimum number of observations during the simulated random patterns:

set system mode fault set random patterns 612 analyze observe report observe data

FastScan and FlexTest Reference Manual, V8.6_4

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Mentor v8.6_4 manual Analyze Observe