Ruggedised Products

With the ever increasing complexity and switching speeds of FPGAs, thermal management presents ever greater engineering challenges. To tackle these challenges Alpha Data has developed cooling solutions for selected products.

• Forced Air Cooling - Provide on board fans to create a continuous airflow over the FPGAs
• Bolt on heatsinks - Increases the surface area for heat dissipation, thus improving the flow of heat from the FPGAs
• Conduction Cooling - When embedded in a system the FPGA board can be bolted directly to the cooling system for the carrier utilising it's cooling system to dissipate the excess heat from the FPGAs

Alpha Data provides three levels of cooling for selected products:

• Air Cooled Commercial (AC0) - Alpha Data's standard board fitted with commercial components, utilises convection cooling to available air in the surrounding system.
• Air Cooled Industrial (AC1) - As AC0 but with industrial components which have a wider operating range and a heatsink is fitted to the board where appropriate
• Conduction Cooled Industrial (CC1) - As AC1 but products are also designed to bolt onto the carrier boards cooling system

Convection Cooling

Where the boards dissipate heat into the surrounding air. To be effective there needs to be sufficient air flow across the board so that the dissipated heat is carried away from the board. Convection cooling can be improved by having a larger surface area to dissipate heat from and/or increased air flow around the board.

Forced Air Cooling

Where there is insufficient air flow through the system the FPGA boards may not be able to dissipate sufficient heat to continue correct operation. By adding fans on or in close proximity to the FPGAs the airflow can be increased across the board, allowing a greater amount of heat to be dissipated from the components under duress.

Heatsinks

If directed air flow over the FPGAs is insufficient to keep them cool then adding additional surface area to dissipate the heat from is the next stage. Alpha Data has developed selected products with the capability of having heatsinks bolted onto them. The heatsinks have direct contact with the FPGAs (thermal paste) allowing a greater flow of heat from the FPGA. The heatsinks themselves provide a much greater surface area over which the heat can be dissipated.

When you need more cooling then a heatsink may be added to the underside of the board (especially if active devices are fitted there).

NB: Adding the heatsink is only one aspect, the airflow has to be sufficient to allow the heatsink to dissipate sufficient heat to minimise the component junction temperatures.

Conduction Cooling

As well as providing a heatsink to improve air cooling some products are designed to utilise conduction cooling so the board and heatsink can be bolted into a system which provides the conduction cooling facility to conduct the heat away from the board. Designed to comply with VITA 20 these copper strips allow the board to be bolted directly onto cooling bars on the carrier.

There are two types of contact bars:

• Primary - Must be provided. These are the three copper strips on the left, middle and right as you look at the board (PMC connectors on your left).
• Secondary - Are optional copper strips and these run along the top and bottom edges of the mezzanine card

These copper strips match up with the cooling bars on the carrier. Creating the conduction path for extracting heat from the board.

Due to Alpha Data FPGA boards allowing the user to plug in a variety of I/O modules the FPGA cards cannot meet all the requirements for the Vita 20 standard. As stated in the standard they will require a modification to the faceplate rib of the carrier. This reduces the contact area and so reduces the cooling capability for the system.

Alpha Data cards which are designed to have no front panel I/O shall be fully complaint to the standard for conduction cooling.

If you have any questions please contact Alpha Data Support

For more information on the operating conditions for the different cooling options read the Alpha Data Environment Specification.