Standard JEDEC Test Models

Your package characterization test environments can now be customized using the JEDEC Test Environment Wizard. Furthermore, your package wizards are now directly “linked” to this new Wizard, so that you can create the package, place it in a suitable test environment, and grid it in a seamless process. You can then import the file into FloTHERM, and click Solve.

If you are not familiar with the JEDEC standards, you can find them in the Free Download Area of the JEDEC website, https://www.jedec.org

Using the JEDEC Test Environment Wizard

The wizard can be started in one of the following ways:

1. By clicking the JEDEC Test Environment menu

2. By clicking the Add Test tab within a library

3. By choosing Put this package in a JEDEC test environment in the last step of a SmartPart Wizard

Note that the first option generates a PDML file of the test environment only, whereas the second and third options generate a PDML file of the package in question placed inside the test environment.

Step 1 - Choose a Test Board and Type

The Wizard allows you the choice of three standard Board Sizes:

• Small Board (114.3mm X 76.2mm)

• Medium Board (114.3mm X 101.6mm)

• Large Board (139.7mm X 127.0mm)

But if you have other PCB libraries (Type = pcb) in your workbench, FloTHERM PACK automatically adds them to the list so that you can specify your own test boards.

For a given board size, you can further choose the Board Type, based on conductivity, as defined by JEDEC:

• High Conductivity (2S2P) 2 signal and 2 power/ground planes

• Low Conductivity (1S0P) 1 signal layer only

For improved accuracy, you will not be able to set the Coverage (%) or Layer Type for the Top Layer of packages identified in “Detailed Trace Modeling”.

Step 2 - Add Vias

You can add vias below the package footprint, if they exist in their particular test board. The vias can be modeled either discretely or as a lumped cuboid with orthotropic conductivity. There is also an option to depopulate your via array.

Step 3 - Choose the Test Environment

You can create the following test environments:

• Still Air (Theta-JA) to estimate Theta-JA, or junction-to-ambient resistance

• Forced Air (Theta-JMA) to estimate Theta-JMA, or junction-to-moving-air resistance at any forced air velocity.

• Ring Cold Plate (Theta-JB) to estimate Theta-JB, or junction-to-board resistance

• Top Cold Plate (Theta-JC) to estimate Theta-JC, or junction-to-case resistance

Step 4 - Choose the Level of Gridding

As a final step, you are asked to choose the level of gridding for your generated model. The levels available are:

• Coarse

• Medium

• Fine

The grid attached to the model will be in the form localized grid constraints for the package and the test board. There will also be overall system grid to ensure there are grid cells in regions far away from the test board.

Downloading and Importing into FloTHERM

Once the last step is reached, generate the test environment (with your package in it, if applicable) by clicking Create Test Environment. A ready-to-solve PDML file is created which you will need to save. This saved file can then be imported into FloTHERM where all you need to do is select Solve and wait for convergence.