The Model option enables you to define a mission profile, design a package, and assign its geometry and material specifications. It also provides selection aids for interconnects, substrates, package types, and mounting technology. You can modify a pre-existing design or create a new design. Several sample package designs are included with the software to get you started. After completing a design, use the Analyze options (see Chapter 7) to test it. If Analyze reveals flaws, return to Model to correct them. If no suitable environments or test/screen files exist, create them in the Environment or Test/Screen Library before using Profile.

6.2.1    Purpose of Mission Profile 

The Profile option enables you to specify the environments and/or stress conditions the package will be exposed to over its mission life.

The environments, and their accompanying parameters, are stored in the Environment Library and the Test/Screen Library. Changes to environment or test/screen parameters must be made using the Library options. Environments or test/screen conditions in which vibration loading is a factor are accompanied by acceleration power spectral density (APSD) charts. However, currently there are no resident failure mechanisms which evaluate the effect of vibration stresses. It is left to the user to input the model he/she feels is the most appropriate. If you are a new CADMP-II user, reading the sections in Chapter 8 on the Environments Library, the Test/Screen Library, the PSD Curves Library, will enable you to better understand Mission Profile.

6.2.2 The Mission Profile Screen

• In the CADMP-II Manager, select the Model option header. The Model menu appears.

• Profiles enables you to load, create, save and delete mission profiles.
• Edit enables you to make changes to a profile.
• Graph enables you to view information graphs.

The Profiles menu contains four commands:

• Load lets you activate an existing mission profile.
• New lets you create new mission profiles.
• Saveas lets you duplicate existing mission profiles.
• Delete lets you discard mission profiles.

• Select the Load command from the Profiles option header menu. A window listing all the existing mission profiles appears (see Figure 3).
Figure 3. The Load command selection window  
• Select a profile. You return to the Mission Profile screen. The active mission profile file name appears in the upper right of the top menu bar.

• Select the New command from the Profiles option header menu. A New File Name box appears in the bottom portion of the screen (see Figure 4).
Figure 4. The New command new file entry window

 

• Type a file name. Click on the new name or press Enter to activate it. The name of the new file appears in the upper right corner of the top level menu bar.

6.2.3.3    The Saveas Command
 
Use Saveas to duplicate an active profile. You can then modify the new file to create a new, similar environment for your package.

• Select the Saveas command from the Profiles option header menu. Make sure the profile which is to be duplicated is active. A box appears, asking you to name the duplicate.
• Type the new name. Press Enter or click on it with the mouse.
• The newly named file becomes active, and its name appears in the upper right corner of the top level menu bar. The old file is no longer active, but is not overwritten.

6.2.3.4    The Delete Command
 
Use Delete to delete profiles. The active profile cannot be deleted.c

• Select the Delete command from the Profiles option header menu. A list of profiles appears.
• Select the profile you want to delete. Press Enter or click on it with the mouse.
• A message appears asking you to confirm the deletion (see Figure 5). Select Yes to confirm, No to cancel and return to the Mission Profile screen.

Attempting to delete the active profile produces an error message. Activate a different profile and then select the previously active profile for deletion.

6.2.4    The Edit Option
 
The Edit option in Mission Profile enables you to specify environments and stress conditions for both new and old profiles. Operation/transportation/storage environments are stored in the Environments Library, test and screening conditions in the Test/Screen Library. The Edit option header menu contains three commands (see Figure 6):

• Change enables you to replace environments and stress conditions with others, change the duration assigned and environment or stress condition, and specify their repeats.
• Add enables you to specify environments and stress conditions from the mission profile.
• Delete enables you to delete environments and stress conditions from the mission profile.

• Select the Change command from the Edit option header menu. An Edit window appears. The active profile name appears in the upper right corner (see Figure 7). In this window you can group or replace environments or stress conditions (listed as E or S, respectively, in the Envir. Type category), view their parameters and APSD graphs, and adjust mission time, as explained on the next page. If there is no data in the mission profile, an error message appears.

Grouping Environments

When a device experiences environment(s) cyclically, you must group the environment(s), and specify the number of repeats (the Group Repeat time below).

• In the Change Mission Profile window, select any field in the environment or stress condition you want in the group. Then select the Repeat Group hot key. The Group Head field changes from - to G, the Group Repeat Time is assigned a value of 2, and the Mission Time field turns blue (see Figure 8).
Figure 8. Grouping environments  
• To change the number of group repeats, select the Group Repeat Time field, and type a new number.

 
• To ungroup an environment or stress condition, select any field. Then select the Repeat Group hot key. The grouping field changes from G to -, the repeat field goes blank, and the blue color disappears.

When you replace environments or stress conditions, you exchange one for another. Use this method to place one last in the list.

• In the Edit window, select the environment or stress condition you want to replace and press the Space bar. A list of environments or stress conditions appears. To view a description of any environment or stress condition, select it and press F1. To view parameters, select the Parameters hot key. See "Viewing Parameters and APSD Graphs" below.

 

• Select the replacement environment or stress condition and press Enter. You return to the Edit window, where the replacement appears. The environment type field will change to E or S for environment or stress condition, respectively.

• In the Edit window, select the environment or stress condition. Then select the Parameters hot key. A read-only parameters window appears (see Figure 9). Press Esc to exit.
Figure 9. The View Parameters Window

 

• To view an APSD graph, select the APSD hot key. The graph appears (see Figure 10). Press Esc to exit.

Change Mission Time

Select the time to be changed. Type the number of hours the device will experience the environment and press Enter.

6.2.4.2    The Add Command

Use Add to include an environment or stress condition and its duration in a mission profile.

• Select the Add command from the Edit option header menu. An Add Environments window appears listing five things: The environmental/stress index number, environmental/stress file name, environmental type, environment description, and the mission duration time (see Figure 11). The index number, which determines what order the environments appear in the profile, cannot be changed. The file name appears after you select an environment or stress condition for addition.
Figure 11. The Add command dialogue window

 

• The Environment Type field is highlighted. Press the Space bar to toggle between Environment and Stress. Press Return to select one of the two. The highlighter moves to the Environment Description field.
• Press the Space bar. A list of all available environments or stress conditions appears. You can view their parameters with the Parameters hot key in the lower left corner of the window. The Parameters window is view only. You can view any ASPD graph by selecting the ASPD hot key. Press Esc to return to the Add Environments window.
• Select and environment of stress condition to add to the mission profile and press Enter to return to the Add Environments window. The file name and description of the chosen environment appears (see Figure 12).
Figure 12. After selecting environment  
• If you want to change the mission time, select the Mission Time field and type a new time.
• To add the environment to the mission profile, select the Accept hot key. Press Esc to cancel.
• Repeat Steps 1-6 to add more environments or stress conditions to the mission profile.

Use Add and Delete in tandem to adjust the order of the environments and stress conditions in the profile.

• Select the Delete command from the Edit option header menu. The Edit window in Figure 13 appears.

• An environment must be tagged before it can be deleted. To tag an environment, highlight it and press the left mouse button or press Enter. A check mark appears next to the environment, indicating it is tagged (see Figure 13). Untag a tagged environment using the same procedure.
• To delete the tagged environment, select Close. Press Esc to cancel. A window asks you to confirm. Select Yes to confirm, No to cancel and return to the Mission Profile screen.

Use the Graph option header to view graphs displaying certain mission profile characteristics. Each graph plots various parameters against time. The graphs enable you to avoid having to view the environment parameters separately.

• Select the Graph option from the Mission Profile screen. The Graph option header menu appears (see Figure 14). Three types of graphs may be viewed:

• Temperature plots the minimum, maximum, and average temperature.
• Temperature Cycle plots only the temperature cycle.
• Relative Humidity plots the minimum, maximum, and average relative humidity (RH) and the RH cycle