User manual

DIGITAL-LOGIC AG MSB900/L Detailed Technical Manual V1.0
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11. THERMAL SPECIFICATIONS
11.1. Thermal Analysis for Case Integration
The MSB900/L has a unique thermal design. Heat sources are located on the bottom side of the PCB.
Usually this means the board will be mounted upside down with the CPU thermally in contact with a heat
sink. Alternatively, the CPU will be in contact with the system enclosure which then works as a heat sink.
The LX900 CPU is rated with a Total Dissipated Power (TDP) of 3.8W maximum and 1.6W typical @ 600
MHz.
The following picture is a thermal analysis of the bottom side. It was taken after one hour of operating (BIOS
screen) at room temperature. There was no heat sink mounted on the CPU.
f
CPU
[MHz]
U
in
[V] T
CPUmax
[°C] T
CS5536max
[°C]
600 12
Pay particular attention when mounting the PC-product in a fully enclosed case/box. The thermal energy will
be stored in the interior of this environment.
If the case has a fan:
• The hot air must be exchanged with cool air from outside using a filtered fan.
• The hot air must be cooled with a heat exchanger.
If the case has no fan or opening to exchange hot air:
• The heat sink of the CPU must be mounted directly to a heat sink integrated in the case. The heat will
be conducted directly through the alloy of the heat sink to the outside.