WebTHERM™ Online Thermal Simulation

The WebTHERM™ online tool simulates the thermal behavior of an electronic printed circuit board with components. Developed through a partnership between National Semiconductor and Flomerics, the world leader in thermal simulation of electronics seller and developer of the software tool FLOTHERM, the WebTHERM tools uses validated thermal models for the components and the reference PCB. The user defines the environment, and the problem is solved using the tool's fast and accurate conduction and radiation solver. The output is a color plot of the PC board under the design's steady-state electrical load conditions. No special hardware is required, just an ordinary Web browser.

The WebTHERM tools helps the user identify heat problems on the printed circuit board early on in the design process and correct the issues before the board goes into production. This can save a lot of time and avoid costly quality accidents.

To use the WebTHERM tools, first create a power supply design in the WEBENCH® online design environment. After choosing a part and creating a design, click on "Analyze a Design" in the WEBENCH navigation header. A "Thermal Simulation" tab will appear. Click there to start up the WebTHERM tool.

Next a picture of the physical layout of your PC board appears in your Web browser, showing the placement of each component and the copper routing, as shown in figure 1 below. There are controls for the board orientation, edge temperature, and airflow direction and speed, which allow the user to adjust parameters for the simulation.

After entering the desired parameters for simulation, the user submits the simulation job. A status screen then appears to allow the user to check the simulation progress. A simulation typically takes two to three minutes to complete, excluding queue time.

After the simulation is complete, the user can view the result, a full color plot of the temperature across the board, as shown in figure 2 below. The temperature of each component is also listed in an accompanying table. If desired, the user can adjust parameters and resubmit the job for simulation.

The WebTHERM tool, and WEBENCH environment, bring powerful design capability to designers. The WebTHERM tool is fully integrated with the WEBENCH environment, and therefore allows the designer to seamlessly qualify their designs from a thermal and electrical standpoint. Integration of these tasks on the Web allows a major improvement in design accuracy and can save a significant amount of time in the design cycle.

Figure 1: Display of Physical Board Layout in the WebTHERM tool

Figure 2: WebTHERM simulation results