System-Level Considerations - VersaLogic BayCat VL-EPM-31ECP Hardware Reference Manual

S -
YSTEM LEVEL
The EPM-31 thermal solutions – either the HDW-412 heat sink alone or with the HDW-407 fan
– are part of the larger thermal system of the application. Other PC/104 boards stacked under the
BayCat and any other nearby heat sources (power supplies or other circuits), all contribute to
how the EPM-31 will perform from a thermal standpoint.
The ambient air surrounding the EPM-31 needs to be maintained at 85 ºC or below. This can
prove to be challenging depending on how and where the EPM-31 is mounted in the end user
system. Standard methods for addressing this requirement include the following:

Provide a typical airflow of 100 linear feet per minute (LFM) / 0.5 linear meters per
second (as described in the section titled EPM-31 Thermal Characterization, beginning
on page 71) within the enclosure

Position the EPM-31 board to allow for convective airflow

Lower the system level temperature requirement as needed
The decision as to which thermal solution to use can be based on several factors including (but
not limited to) the following:

Number of CPU cores in the SoC (single, dual, or quad)

CPU core program utilization

Temperature range within which the EPM-31 will be operated

Air movement (or lack of air movement)

Video processing intensity

Memory access demands

High speed I/O usage (PCIe, USB 3.0, SATA usage)
Most of these factors involve the demands of the user application on the EPM-31 and cannot be
isolated from the overall thermal performance. Due to the interaction of the user application, the
BayCat thermal solution, and the overall environment of the end system, thermal performance
cannot be rigidly defined.
EPM-31 Hardware Reference Manual
C
ONSIDERATIONS
Thermal Considerations
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