VersaLogic Viper VL-EBX-38EBP, Hardware Reference Manual

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Thermal Considerations
EBX-38 Hardware Reference Manual
63
T
HERMAL
S
PECIFICATIONS
, R
ESTRICTIONS
,
AND
C
ONDITIONS
Graphical test data is in the section titled EBX-38 Thermal Characterization, beginning on page
64. Refer to that section for the details behind these specifications. These specifications are the
thermal limits for using the EBX-38 with one of the defined thermal solutions.
Due to the unknown nature of the entire thermal system, or the performance requirement of the
application, VersaLogic cannot recommend a particular thermal solution. This information is
provided for user guidance in the design of their overall thermal system solution.
Table 33. Absolute Minimum and Maximum Air Temperatures
Board With Heat Plate
With Heat Sink
(HDW-406)
With Heat Sink + Fan
(HDW-413)
VL-EPMe-42EAP -40 ° to +85 °C -40 ° to +85 °C -40 ° to +85 °C
VL-EPMe-42EBP -40 ° to +85 °C -40 ° to +85 °C -40 ° to +85 °C
VL-EPMe-42ECP -40 ° to +85 °C -40 ° to +85 °C -40 ° to +85 °C
O
VERALL
R
ESTRICTIONS AND
C
ONDITIONS

Ranges shown assume less than 90% CPU utilization.

Keep the maximum CPU core temperature below 100ºC.

The ambient air surrounding the EBX-38 needs to be maintained at 85 ºC or below. This
includes the space between this CPU board and any board it is stacked on top of it.
Included is the space beneath an installed Mini PCIe expansion board and the installed
SODIMM. A recommended overall air flow of 100 Linear Feet per Minute (LFM) / 0.5
Linear Meters per Second (LMS) addresses this requirement. If this air flow is not
provided, other means to keep the adjacent air at 85 ºC or below must be implemented.
H
EAT
P
LATE
O
NLY
R
ESTRICTIONS AND
C
ONDITIONS
:

The heat plate must be kept below 90 °C. This applies to a heat plate mounted directly to
another surface.
H
EAT
S
INK
O
NLY
C
ONSIDERATIONS
:

At 85°C air temperature and 90% CPU utilization, there will be little – if any – thermal
margin to a CPU core temperature of 100 °C or the passive trip point (see test data). If
this is the use case, consider adding a fan or other additional air flow.
H
EAT
S
INK WITH
F
AN
C
ONSIDERATIONS
:

The heat sink and fan combination cools the CPU when it is running in high temperature
environments, or when the application software is heavily utilizing the CPU or video
circuitry. The fan assists in cooling the heat sink and provides additional air movement
within the system.

Integrator’s Note:
The ambient air surrounding the EBX-38 needs to be maintained at 85 ºC or below.