Cpu Emergency Thermal Supervision - Kontron CP6500-V User Manual

System Considerations
7.1.2

CPU Emergency Thermal Supervision

This function cannot be enabled or disabled in the BIOS. It is always enabled to ensure that the
processor is protected in any event.
Assertion of Thermtrip indicates that the processor junction temperature has reached a level
beyond which permanent silicon damage may occur. Measurement of the temperature is ac-
complished through an internal thermal sensor which is configured to trip at approximately
135°C. Upon assertion of Thermtrip, the processor will shut off its internal clocks (thus halting
program execution) in an attempt to reduce the processor junction temperature. Once activat-
ed, Thermtrip remains latched until the CP6500-V undergoes a cold restart is performed (all
power off and then on again).
7.1.3 Thermal Management Recommendations
If the CP6500-V is operated in a properly configured CompactPCI environment with enough air
flow, there is no need to enable the Thermal Management function. However, sometimes the
system environment is not optimized for a Celeron processor board and this requires thermal
protection to guarantee a stable system. The Thermal Management feature allows system de-
signers to design lower cost thermal solutions without compromising system integrity or reliabil-
ity.
In this case the external Thermal Monitor should be enabled. This monitor protects the proces-
sor and the system against excessive temperatures. In this configuration the clocks will be
switched on and off. At a 50% duty cycle, for example, the average power dissipation can drop
by up to 50%. In this case, the processor performance also drops by about 50% since program
execution halts when the clocks are removed.
Warning!
For Benchmarks and performance tests all Thermal Management functions
should be disabled, if enabled the results will be erroneous due to the thermal
power reduction.
7.2 Active Thermal Regulation
The thermal management concept of the CP6500-V also encompasses active thermal regula-
tion. For this processor, a specifically designed heat sink is employed to ensure the best pos-
sible basis for operational stability and long term reliability. Coupled together with system
chassis which provide variable configurations for forced air flow, controlled active thermal en-
ergy dissipation is guaranteed.
7.2.1 Heat Sinks
The CP6500-V is fitted with an optimally designed heat sink. The physical size, shape, and con-
struction ensures the best possible thermal resistance (R
cifically designed to efficiently support forced air flow concepts as found in a modern
CompactPCI system chassis.
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CP6500-V
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