Intel Atom Processor N270 AU80586GE025D Fiche De Données

Datasheet  

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Thermal Monitor feature. The Intel Thermal Monitor can be configured to generate an 

interrupt upon the assertion or de-assertion of PROCHOT#.  

PROCHOT# will not be asserted when the processor is in the Stop Grant, Sleep, Deep 

Sleep, and Deeper Sleep low power states; hence, the thermal diode reading must be 

used as a safeguard to maintain the processor junction temperature within maximum 

specification. If the platform thermal solution is not able to maintain the processor 

junction temperature within the maximum specification, the system must initiate an 

orderly shutdown to prevent damage. If the processor enters one of the above low 

power states with PROCHOT# already asserted, PROCHOT# will remain asserted until 

the processor exits the low power state and the processor junction temperature drops 

below the thermal trip point.  

If Intel Thermal Monitor automatic mode is disabled, the processor will be operating 

out of specification. Regardless of enabling the automatic or on-demand modes, in the 

event of a catastrophic cooling failure, the processor will automatically shut down 

when the silicon has reached a temperature of approximately 125°C. At this point the 

THERMTRIP# signal will go active. THERMTRIP# activation is independent of processor 

activity and does not generate any bus cycles. When THERMTRIP# is asserted, the 
processor core voltage must be shut down within the time specified in Chapter 

3. 

The processor also contains an on-die Digital Thermal Sensor (DTS) that is read via an 

MSR (no I/O interface). The DTS is only valid while the processor is in the normal 

operating state (the Normal package level low power state). 

Unlike traditional thermal devices, the DTS outputs a temperature relative to the 

maximum supported operating temperature of the processor (T

J_max

). It is the 

responsibility of software to convert the relative temperature to an absolute 

temperature. The temperature returned by the DTS will always be at or below T

J_max

. 

Catastrophic temperature conditions are detectable via an Out Of Spec status bit. This 

bit is also part of the DTS MSR. When this bit is set, the processor is operating out of 

specification and immediate shutdown of the system should occur. The processor 

operation and code execution is not ensured once the activation of the “Out of Spec” 

status bit is set.  

The DTS-relative temperature readout corresponds to the Intel Thermal Monitor-1 and 

Intel Thermal Monitor -2 trigger point. When the DTS indicates maximum processor 

core temperature has been reached, the Intel Thermal Monitor-1 or Intel Thermal 

Monitor-2 hardware thermal control mechanism will activate. The DTS and Intel 

Thermal Monitor-1/Intel Thermal Monitor-2 temperature may not correspond to the 

thermal diode reading since the thermal diode is located in a separate portion of the 

die and thermal gradient between the individual core DTS. Additionally, the thermal 

gradient from DTS to thermal diode can vary substantially due to changes in processor 

power, mechanical and thermal attach, and software application. The system designer 

is required to use the DTS to ensure proper operation of the processor within its 

temperature operating specifications. 

Changes to the temperature can be detected via two programmable thresholds located 

in the processor MSRs. These thresholds have the capability of generating interrupts 

via the core's local APIC.