Intel Atom Processor N270 AU80586GE025D Data Sheet

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 Datasheet 

Note:  The digital thermal sensor (DTS) accuracy is in the order of -5°C ~ +10°C around 

90°C; it deteriorates to ±10°C at 50°C. The DTS temperature reading saturates at 
some temperature below 50°C. Any DTS reading below 50°C should be considered to 
indicate only a temperature below 50°C and not a specific temperature. External 
thermal sensor with “BJT” model is required to read thermal diode temperature. 

Overheat detection is performed by monitoring the processor temperature and 

temperature gradient. This feature is intended for graceful shut down before the 

THERMTRIP# is activated. If the processor’s Intel Thermal Monitor-1 or Intel Thermal 

Monitor-2 are triggered and the temperature remains high, an “Out Of Spec” status 

and sticky bit are latched in the status MSR register and generates thermal interrupt.  

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

temperature has reached its maximum operating temperature. If Intel Thermal 

Monitor-1 or Intel Thermal Monitor-2 is enabled, then the TCC will be active when 

PROCHOT# is asserted. The processor can be configured to generate an interrupt 

upon the assertion or de-assertion of PROCHOT#.  

The processor implements a bi-directional PROCHOT# capability to allow system 

designs to protect various components from overheating situations. The PROCHOT# 

signal is bi-directional in that it can either signal when the processor has reached its 

maximum operating temperature or be driven from an external source to activate the 

TCC. The ability to activate the TCC via PROCHOT# can provide a means for thermal 

protection of system components. 

Only a single PROCHOT# pin exists at a package level of the processor. When the 

core's thermal sensor trips, the PROCHOT# signal will be driven by the processor 

package. If only Intel Thermal Monitor-1 is enabled, PROCHOT# will be asserted and 

only the core that is above TCC temperature trip point will have its core clocks 

modulated. If Intel Thermal Monitor-2 is enabled and the core is above TCC 

temperature trip point, it will enter the lowest programmed Intel Thermal Monitor-2 

performance state. It is important to note that Intel recommends both Intel Thermal 

Monitor-1 and Intel Thermal Monitor-2 to be enabled. 

When PROCHOT# is driven by an external agent and if only Intel Thermal Monitor-1 is 

enabled on the core, then the processor core will have the clocks modulated. If Intel 

Thermal Monitor-2 is enabled, then the processor core will enter the lowest 

programmed Intel Thermal Monitor-2 performance state. It should be noted that Force 

Intel Thermal Monitor-1 on Intel Thermal Monitor-2, enabled via BIOS, does not have 

any effect on external PROCHOT#. If PROCHOT# is driven by an external agent when 

Intel Thermal Monitor-1, Intel Thermal Monitor-2, and Force Intel Thermal Monitor-1 

on Intel Thermal Monitor-2 are all enabled, then the processor will still apply only Intel 

Thermal Monitor-2. 

PROCHOT# may be used for thermal protection of voltage regulators (VR). System 

designers can create a circuit to monitor the VR temperature and activate the TCC 

when the temperature limit of the VR is reached. By asserting PROCHOT# (pulled-low) 

and activating the TCC, the VR will cool down as a result of reduced processor power