PCB Thermal Design, Simulation & Analysis
This PCB thermal analysis tool outputs board temperature and gradient maps, component and junction temperatures—plus the amount by which those temperatures exceed their respective limits.
HyperLynx: PCB thermal analysis software models electronic boards with up to 3,000 components on each side considering conduction, convection, and radiation. HyperLynx Thermal is used routinely in various industrial applications, including Aerospace, Computer, Networking, Telecom, Industrial Control, Instrumentation, and Automotive electronics.
Features and Benefits: PCB Thermal
- Models double-sided multi-layered boards with up to 3,000 components per side
- Interfaces to the leading ECAD placement packages for easy file transfer
- Improves reliability predictions with precise calculation of junction temperatures
- Provides impressive color maps that make outstanding reports
- Supports all major global electronic industries
- Allows for intuitive and ease of use with Windows-based software
Our users, experimental wind tunnel tests, and infrared image tests consistently validate an accuracy of +/-10%. The analysis fully performs 3-Dimensional modeling of the complex flow and thermal fields based on heat conduction, convection, and radiation. Finite difference schemes with self-adaptive locally refined meshes are used in the computation to produce extremely fast, yet accurate results. The analysis needs only 1/50 of the time of equivalent finite element programs. Typically, an analysis takes 12 seconds for a board of 100 components run on a 100 MHz Pentium PC.
Automatic interfaces with Expedition, PADS, Board Station, Allegro, CADSTAR, OrCAD, P-CAD, Protel, Visula, and other placement packages are available. Outputs colorful temperature and gradient maps that are easy to read and enhance reports.
HyperLynx Thermal can evaluate boards with multiple layers and irregular shapes. The board can be placed at the edge or interior of a cabinet, anchored by screws to heat sinks, cooled through wedge locks at the edges, in a sealed compartment, or in an open system with forced convection. The flow field can be natural or forced convection, and closed systems can be cooled by heat exchangers. Effects of gravity, air pressures, and flow directions are modeled. Heat sinks, heat pipes, chip fans, and conduction pads can be attached to components.
The failure rates of components are exponentially proportional to the junction temperatures and dependent on the I.C. technology. Therefore, different types of components have different limiting temperatures. HyperLynx Thermal allows the user to input these limiting temperatures, and provides an output screen to monitor the deviations from the specified limits.
Board Temperature Map
The temperature map predicted by Mentor Graphics reveals the heat conduction phenomena in the board. Since the thermal expansion is proportional to the temperature, the high temperature regions may bulge or warp during operation. This may cause the pins of surface mount devices to detach. HyperLynx Thermal identifies the hot spots on the board during the design stage.
Temperature Gradient
A color map of temperature gradients across the board is also provided as output. A severe temperature gradient usually induces high thermal stress due to the significant differential in thermal expansion. High thermal stress areas are also locations where board cracking or warping is most likely to occur. Mentor Graphics alerts you to potential trouble spots on your board.
Applications: PCB Thermal
Space/Avionic
A large number of Mentor Graphics users are in the Space/Avionic industries. These industries include satellites, space stations, airplanes, and missiles. The figure shows a typical board used in a satellite application. The board relies upon thermal screws and wedge locks at the upper and lower edges to conduct the heat to the sink. Thermal radiation is also very important in these designs.
Telecom/Industrial
Control High reliability is a demand in these industry segments where large numbers of complex boards are encountered. The figure shows a board in a cardcage at natural convection cooling. Heat sinks have been used to cool some components. ECAD interfaces give a perfect translation of component placement, and library information to speed the setup process for these densely packed boards.
Computer/Instrument
These boards frequently have a few components, such as CPUs, with high power dissipation. The boards are usually very large with many components. Chip fans, heat sinks, or local impingement jets are used along with strong forced convection as cooling methods. The figure shows the analysis of a large mother board. Again, the ECAD interface is essential for these boards because of the vast number of components.
Automotive
In many automotive applications, high currents pass through heavy traces on the board and generate significant heat. A Trace Version of Hyperlynx Thermal is available for these types of special boards. The hot traces are modeled on the board using a power density factor. Some typical results for an automotive trace application are shown in the figure.
Power Supplies
Power supplies have many tall components that generate significant amounts of power. These components also create air flow blockage effects which could be severe. A horizontal power supply operating at natural convection is simulated in the figure. Although the transformer has high power, its temperature is low due to the large surface area. The hot components are the ones with medium power and medium size.
Validations: PCB Thermal
Case 1
Board with 12 Blocks
The simplest test case is of 12 power blocks on a board, where each block is 0.25 inches high, except the middle one in the second row from the bottom, which is 0.75 inches high. The power of each block is 1 watt and the board is vertically oriented at natural convection. The data comparisons listed in Table 1 are very satisfactory.
| Block Number | Measurement Results (°C) | HyperLynx Thermal Prediction (°C ) |
|---|---|---|
| 1 | 57.0 | 56.3 |
| 2 | 58.0 | 60.6 |
| 3 | 69.4 | 70.0 |
| 4 | 66.5 | 64.7 |
| 5 | 54.2 | 52.9 |
| 6 | 60.9 | 60.9 |
| 7 | 64.8 | 64.0 |
| 8 | 61.1 | 58.9 |
Case 2
Infrared of Total Board
An entire board infrared comparison is made. The powers of components are different. Infrared measurements are made for the board at the real operational condition of natural convection. The actual board has resistors and capacitors located on the back side. A quick first time run of the case was performed with only the major components on the front side modeled. The comparison temperatures of 20 randomly picked IC components across the board are listed in the table below and in general show good accuracy.
| Number | IR Scan | HyperLynx Thermal |
|---|---|---|
| 1 | 82.8 | 81.6 |
| 2 | 82.9 | 85.0 |
| 3 | 84.7 | 84.2 |
| 4 | 84.3 | 83.7 |
| 5 | 90.4 | 90.3 |
| 6 | 82.7 | 84.0 |
| 7 | 81.7 | 81.3 |
| 8 | 81.1 | 82.8 |
| 9 | 79.1 | 83.3 |
| 11 | 88.1 | 89.0 |
| 12 | 82.9 | 80.8 |
| 13 | 82.3 | 79.9 |
| 14 | 86.6 | 84.4 |
| 15 | 77.7 | 78.9 |
| 16 | 76.4 | 77.4 |
| 17 | 75.5 | 76.4 |
| 18 | 77.8 | 76.2 |
| 19 | 73.1 | 75.5 |
| 20 | 74.2 | 74.8 |
Case 3
Aerospace Board Tests
An example case selected to illustrate the modeling techniques in aerospace thermal design is an engine controller design by AlliedSignal Aerospace. The engine controller is subjected to severe environmental constraints. After all the simulation and any design iterations were completed on the engine controller, an initial prototype was developed and tested. Controlled testing was conducted on the design, and data was collected for the many components with significant power dissipation. The test was conducted in a temperature chamber with a 71C ambient, and thermocouples were used to record the temperature rise of the components. The table below shows the measured results versus the HyperLynx Thermal prediction.
| Reference Designator | Test Data Junction Temp | HyperLynx Thermal-Prediction Junction Temp |
|---|---|---|
| cr9 | 97.20 | 98.90 |
| cr14 | 91.70 | 92.00 |
| cr20 | 85.23 | 86.30 |
| g15 | 85.99 | 84.70 |
| u12 | 88.40 | 87.70 |
| u24 | 88.37 | 88.90 |
| u25 | 86.67 | 88.40 |
| u31 | 89.50 | 87.60 |
| u32 | 87.90 | 89.40 |
| u34 | 89.90 | 92.70 |
| u44 | 87.75 | 88.30 |
| u50 | 88.11 | 89.40 |
| u53 | 86.05 | 87.30 |
| u54 | 85.95 | 86.30 |
| u56 | 88.05 | 88.60 |
Datasheets
- HyperLynx Thermal (PDF, 181kb)
Contact Mentor Graphics
- HyperLynx: PCB Thermal Analysis Info Request or call toll free: 1-800-547-3000