Kontron COMe-cOHXX - Manual (Page 54)

Kontron COMe-cOH2/COMe-cOH6 User’s Guide
www.kontron.com
49
6 Design Considerations
6.1 Thermal Management
An optional heat spreader plate assembly is available from Kontron Embedded
Modules for the COMe-cOH# COM. The heat spreader plate on top of this
assembly is NOT a heat sink. It works as a COM Express®-standard thermal
interface to be used with a heat sink or other cooling device.
External cooling must be provided to maintain the heat spreader plate at
proper operating temperatures. Under worst-case conditions, the cooling
mechanism must maintain an ambient air and heat spreader plate temperature of
60° C or less.
The aluminum slugs and thermal pads on the underside of the heat spreader
assembly implement thermal interfaces between the heat spreader plate and the
major heat-generating components on the COMe-cOH#. About 80 percent of the
power dissipated within the module is conducted to the heat spreader plate
and can be removed by the cooling solution.
Kontron also has defined a passive heat sink that can be used in place of the
heat spreader plate to provide additional cooling. You can use many thermal-
management solutions with the heat spreader plates, including active and
passive approaches. The optimum cooling solution varies, depending on the COM
Express® application and environmental conditions and the module is fully
functional at the full -40C to +85C temperature even without the heat
spreader plate or the passive heat sink. Drawings for both the heat spreader
plate and the passive heat sink are available on request. Also, see the PICMG
COM Express® Design Guide on the PICMG website for further information about
thermal management.
6.2 Heat Spreader Dimensions
Documentation for the COMe-cOH# COM heat spreader and cooling solutions is
provided at http://emdcustomersection.kontron.com .
6.3 Onboard Fan Connector
This section describes how to connect an optional fan for active cooling to a
header located directly on the COMe-cOH# COM.