Intel Atom Processor N270 AU80586GE025D Fiche De Données

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 Datasheet 

limit and subsequently searches for the highest possible operating point. Please 

ensure this feature is enabled and supported in the BIOS. Also with EMTTM 

by the processor.  

Intel Thermal Monitor-1, Intel Thermal Monitor-2, and EMTTM features are collectively 

referred to as Adaptive Thermal Monitoring features. 

Intel Thermal Monitor-1 and Intel Thermal Monitor-2 can co-exist within the 

processor. If both Intel Thermal Monitor-1 and Intel Thermal Monitor-2 bits are 

enabled in the auto-throttle MSR, Intel Thermal Monitor-2 will take precedence over 

Intel Thermal Monitor-1. However, if Force Intel Thermal Monitor-1 over Intel Thermal 

Monitor-2 is enabled in MSRs via BIOS and Intel Thermal Monitor-2 is not sufficient to 

cool the processor below the maximum operating temperature, then Intel Thermal 

Monitor-1 will also activate to help cool down the processor.  

If a processor load based Enhanced Intel SpeedStep Technology transition (through 

MSR write) is initiated when a Intel Thermal Monitor-2 period is active, there are two 

possible results: 

• 

If the processor load based Enhanced Intel SpeedStep technology transition target 

frequency is higher than the Intel Thermal Monitor-2 transition based target 

frequency, the processor load-based transition will be deferred until the Intel 

Thermal Monitor-2 event has been completed. 

• 

If the processor load-based Enhanced Intel SpeedStep technology transition target 

frequency is lower than the Intel Thermal Monitor-2 transition based target 

frequency, the processor will transition to the processor load-based Enhanced 

Intel SpeedStep technology target frequency point. 

The TCC may also be activated via on-demand mode. If bit 4 of the ACPI Intel 

Thermal Monitor control register is written to a 1, the TCC will be activated 

immediately independent of the processor temperature. When using on-demand mode 

to activate the TCC, the duty cycle of the clock modulation is programmable via bits 

3:1 of the same ACPI Intel Thermal Monitor control register. In automatic mode, the 

duty cycle is fixed at 50% on, 50% off, however in on-demand mode, the duty cycle 

can be programmed from 12.5% on/ 87.5% off, to 87.5% on/12.5% off in 12.5% 

increments. On-demand mode may be used at the same time automatic mode is 

enabled; however, if the system tries to enable the TCC via on-demand mode at the 

same time automatic mode is enabled and a high temperature condition exists, 

automatic mode will take precedence.  

An external signal, PROCHOT# (processor hot) is asserted when the processor detects 

that its temperature is above the thermal trip point. Bus snooping and interrupt 

latching are also active while the TCC is active.  

Besides the thermal sensor and thermal control circuit, the Intel Thermal Monitor also 

includes one ACPI register, one performance counter register, three MSR, and one I/O 

pin (PROCHOT#). All are available to monitor and control the state of the Intel