FIC A360 Manuel D’Utilisation

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Software Functional Overview 
 
FIC A360 Service Manual 
3-33
 
Before disabling power, platform designers should incorporate some time that allows the OS 
to run its critical shutdown operation. There is no requirement for a minimum shutdown 
operation window that commences immediately after the temperature reaches _CRT.  This is 
because 
 
−  Heat might rise rapidly in some systems and slower on others, depending on casing 
design and environmental factors. 
−  Shutdown can take several minutes on a server and only a few short seconds on a 
hand-held device. 
 
Because of this indistinct discrepancy and the fact that a critical heat situation is a remarkably 
rare occurrence, ACPI does not specify a target window for a safe shutdown. It is entirely up 
to the OEM to build in a safe buffer that it sees fit for the target platform. 
 
3.5.17  Other Implementation Of Thermal Controllable 
Devices 
The ACPI thermal event model is flexible enough to accommodate control of almost any 
system device capable of controlling heat. For example, if a mobile PC requires the battery 
charger to reduce the charging rate in order to reduce heat it can be seamlessly implemented 
as an ACPI cooling device. Associating the charger as an active cooling device and reporting 
to the OS target temperatures that will enable or disable the power resource to the device do 
this.  Figure as following illustrates the implementation. Because the example does not create 
noise, this will be an implementation of silence mode. 
 
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_AC0
_PSV
_CRT
_AC1
Throttle CPU
Fan on/off
Reduce charge
rate
 
 
Figure 3-5  
Other Thermal Control 
 
3.5.18  Thermal Control Methods 
Control methods and objects related to thermal management are listed in the table below.