User guide

User Guide CC3-CAJUN • Low Power CompactPCI CPU
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EKF Elektronik GmbH • Philipp-Reis-Str. 4 • 59065 Hamm • Germany
Tel. [phone] • Fax. [phone] • [e-mail] • www.ekf.com
Thermal Considerations
In order to avoid malfunctioning of the CC3-CAJUN, take care of appropriate cooling of the
processor and system, e.g. by a cooling fan suitable to the maximum power consumption of the
CPU chip actually in use. Please note, that the processors temperature is steadily measured by a
special controller (MAX1617), attached to the onboard SMBus
®
(System Management Bus). The
processor core (die) temperature is signalled by the forward voltage of a CPU integrated diode.
A second diode internal to the MAX1617 allows for acquisition of the boards surface
temperature. The programmable over-temperature alarm allows to trigger the SMBus alert line
in order to avoid overheating. A suitable software to display both, the die temperature, as well
as the board temperature, is MBM (Motherboard Monitor), which can be downloaded from the
web. After installation, both temperatures can be observed permanently from the Windows
system tray.
By default, the CC3-CAJUN is equipped with a passive heatsink. Its height takes into account the
4HP limitation in mounting space of a CPCI board. In addition, a forced vertical airflow through
the system enclosure (e.g. bottom mount fan unit) is strongly recommended (>15m
3
/h or
200LFM around the CPU slot). As an exception, the CC3-1-CAJUN (ULV Celeron 400MHz) can be
operated with natural convection only. Be sure to thoroughly discuss your actual cooling needs
with EKF. Generally, the faster the CPU speed the higher its power consumption. For higher
ambient temperatures, consider increasing the forced airflow to 400 or 600LFM. A non-
standard heatsink also could improve (lower) the thermal resistance between the die and the
environment (requires more than 4HP board pitch, depending from the heatsink in use).
The maximum power consumption and operating temperature of a particular processor can be
derived from the tables below. Fortunately, the power consumption is by far lower when
executing typical Windows or Linux tasks. The heat dissipation increases especially when
rendering software is executed, e.g. the Acrobat Distiller. EKF tests the CC3-CAJUN by running
a proprietary Intel tool for generating the maximum stress to the processor.
ULV Celeron® 0.13µ Processors Power Consumption and Die Temperature
Processor Speed Typ. Power Max. Power Die Temperature
Celeron 400MHz 3.40W 4.23W 0-100°C
Celeron 650MHz 7.00W 8.30W 0-100°C
LV Pentium® III 0.13µ Processors Power Consumption and Die Temperature
Processor Speed Typ. Power Max. Power Die Temperature
Pentium III 800MHz 11.2W 0-100°
Pentium III 933MHz 12.2W 0-100°
The CC3-CAJUN can be equipped with either a heatsink according to the option 2 described in
the Intel Thermal Design Guide, which must be fixed by four mounting fasteners, or a snap-on
heat spreader, which is fixed by a clip directly to the BGA.