Abstract:
The present invention provides a system, apparatus and method for determining a test coverage for a device by receiving test data from a test platform or development tool, processing the test data to determine or predict the test coverage for the device, and storing the test data and test coverage in a standard format. The test data includes the results of two or more tests on the device.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates generally to the field of test engineering and, more particularly, to a test coverage analysis system.  
         BACKGROUND OF THE INVENTION  
         [0002]    One of the more difficult tasks to perform in Test Engineering is to determine or predict the test coverage of a device under test (“DUT”) and unit under test (“UUT”) on an in-circuit test (“ICT”) platform or development tool. Currently, the process to extract the test data from the test platform or development tool and manipulate that data into a coverage report can take several days. Because this process is performed manually, there are also many opportunities for mistakes. Development tools that are now available do not have any built-in predicted coverage analysis tools. Also, the in-circuit testers&#39; test analysis tools can make incorrect assumptions on coverage, resulting in inaccurate test coverage reports. Accordingly, there is a need to for a test coverage analysis system that overcomes these problems.  
         SUMMARY OF THE INVENTION  
         [0003]    The present invention automates the process of generating test coverage reports. By minimizing the human intervention, the present invention minimizes the time required to generate a test coverage report and minimizes the errors in the generated reports. This allows feedback to improve in-circuit test coverage to be obtained and utilized in a more efficient and timely manner.  
           [0004]    More specifically, the present invention provides a method for determining a test coverage for a device by receiving test data from a test platform or development tool, processing the test data to determine or predict the test coverage for the device, and storing the test data and test coverage in a standard format. The test data includes the results of two or more tests on the device.  
           [0005]    In addition, the present invention provides a method of measuring the actual and predicted results against each other to determine the accuracy of the predicted test coverage. This method uses the standard format test coverage data that was stored for the DUT.  
           [0006]    The present invention also provides an apparatus for determining a test coverage for a device that includes an interface, a processor and a memory. The interface extracts test data from a test platform or development tool. The test data includes the two or more tests on the device. The processor is communicably linked to the interface and processes the test data to determine or predict the test coverage for the device. The memory is communicably linked to the processor and stores the test data and test coverage in a standard format.  
           [0007]    In addition, the present invention provides a system for determining a test coverage for a device that includes a test platform or development tool, an interface, and a memory. The test platform or development tool generates test data, which includes the results of two or more tests on the device. The interface extracts test data from a test platform or development tool. The test data includes the two or more tests on the device. The processor is communicably linked to the interface and processes the test data to determine or predict the test coverage for the device. The memory is communicably linked to the processor and stores the test data and test coverage in a standard format.  
           [0008]    The present invention also provides a computer program embodied on a computer readable medium for determining a test coverage for a device. The computer program includes a code segment for receiving test data from a test platform or development tool, a code segment for processing the test data to determine or predict the test coverage for the device, and a code segment for storing the test data and test coverage in a standard format. The test data includes results of two or more tests on the device. 
       
    
    
       [0009]    Other features and advantages of the present invention will be apparent to those of ordinary skill in the art upon reference to the following detailed description taken in conjunction with the accompanying drawings.  
       BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]    The above and further advantages of the invention may be better understood by referring to the following description in conjunction with the accompanying drawings, in which:  
         [0011]    [0011]FIG. 1 is a block diagram of a preferred embodiment of the present invention;  
         [0012]    [0012]FIG. 2 is an illustration of a first embodiment of a standard format of the present invention; and  
         [0013]    [0013]FIG. 3 is an illustration of a second embodiment of a standard format of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0014]    While the making and using of various embodiments of the present invention are discussed in detail below, it should be appreciated that the present invention provides many applicable inventive concepts which can be embodied in a wide variety of specific contexts. The specific embodiments discussed herein are merely illustrative of specific ways to make and use the invention and do not delimit the scope of the invention. The discussion herein relates to test engineering, specifically to automating the processing of test data to produce test coverage reports.  
         [0015]    The present invention automates the process of generating test coverage reports. By minimizing the human intervention, the present invention minimizes the time required to generate a test coverage report and minimizes the errors in the generated reports. This allows feedback to improve in-circuit test coverage to be obtained and utilized in a more efficient and timely manner.  
         [0016]    The present invention extracts test data from a test platform or development tool, such as Agilent 3173 or FabMaster, and processes that data into a standard presentation format. The processing may involve storing the raw test data in a computer readable structure such as a database. The standard presentation format can be, for example, a spreadsheet.  
         [0017]    [0017]FIG. 1 is a block diagram of a preferred embodiment of the present invention  100 . Platform  110  contains the test data. Possible inputs  112 ,  114 ,  116 ,  118 ,  120  and  122  indicate representative platforms from which test data can be obtained. These inputs  112 ,  114 ,  116 ,  118 ,  120  and  122  can be from in-circuit testers such as Agilent  116  or from development tools such as FabMaster  122  or from a platform not shown herein. Inputs  112 ,  114 ,  116 ,  118 ,  120  and  122  are intended solely as examples and should not be taken to limit the possible inputs to those shown in block  110 , FIG. 1. Each type of platform  110  has a standard ASCII file or report that can be exported from its proprietary database. Input processor  130  exports the data from platform  110 . This export can be accomplished by accessing the standard ASCII files or reports. Each platform  110  can require a customized input processor  130  in order to access the data. Input processor  130  then stores the exported test data in test data database  140 . Test data database  140  can be made by any database tool or platform. Alternative computer readable storage structures, such as spreadsheets and text files, can be used instead of a database. Output processor  150  exports the data from the storage structure, test data database  140 , into a standard presentation format, such as a standard test coverage report  160 . Alternative standard presentation formats, such as spreadsheets and text files, can be used.  
         [0018]    [0018]FIGS. 2 and 3 illustrate embodiments of a standard format of the present invention. Both are displayed in spreadsheet format although either may be presented in an alternative form, such as a text file. FIG. 2 illustrates a sample summary test coverage report that displays the results of calculations performed on the detailed data. FIG. 3 illustrates a sample detailed test coverage report that lists each part tested and specific test data for each. Color coding can also be integrated into the standard presentation format to draw immediate attention to areas that do not attain an acceptable rating.  
         [0019]    More specifically, FIG. 2 includes the project name  202 , CCA#  204 , Date  206 , Test Engineer Name  208 , CCA Name  210  and ICT Testability Effectiveness (Predicted Coverage—CAD Complete)  212 . The possible opens  214 , possible shorts  216 , possible wrong parts  218 , possible missing parts  220 , possible clocked incorrectly  222 , and total possible  244  for the tested device are listed. The testable opens  224 , testable shorts  226 , testable wrong parts  228 , testable missing parts  230 , testable clocked incorrectly  232 , and total testable  246  for the tested device are listed. The percentage opens  234 , percentage shorts  236 , percentage wrong parts  238 , percentage missing parts  240 , percentage clocked incorrectly  242 , and total percentage  248  for the tested device are listed. A color code key  250  is provided to show that greater that 70% test coverage is acceptable, between 50% and 70% test coverage is marginal and less than 50% test coverage is poor. The Estimated DPMO  252 , Estimated DPU  254 , Estimated FPY  256 , Estimated Escaping DPU  258  and Estimated Final Yield  260  for the Assembly DPMO is also provided.  
         [0020]    [0020]FIG. 3 provides Bill of Material (“BOM”) information  302 , mechanical information  304 , electrical information  306 , probe information  308 , test strategy (# of pins)  310 , possible defects  312  and testable defects  314  for the device. The Bom information  302  includes the reference designator  320  and part number  322  for the device. The mechanical information  304  includes the package code  324  and the number of pins  326  for the device. The electrical information  306  includes the device type  328  and the device value  330 . The probe information  308  includes the number of pins without probes  332  and the number of power pins  334 . The test strategy (# of pins)  310  includes RLC  336 , parallel tested  338 , diode/transistor  340 , connection check  342 , test jet  344 , capacitor check  346 , power (analog)  348  and power (digital)  350 . The possible defects  312  includes shorts  352 , opens  354 , wrong part  356 , missing part  358  and clocked incorrectly  360 . The testable defects  314  includes shorts  362 , opens  364 , wrong part  366 , missing part  368  and clocked incorrectly  370 . Each of the rows  372  contain the data for a device.  
         [0021]    Although preferred embodiments of the present invention have been described in detail, it will be understood by those skilled in the art that various modifications can be made therein without departing from the spirit and scope of the invention as set forth in the appended claims.