Intel i3-4360T CM8064601481958 User Manual

When the Digital Temperature Sensor (DTS) reaches a value of 0 (DTS temperatures

reported using PECI may not equal zero when PROCHOT# is activated), the TCC will

be activated and the PROCHOT# signal will be asserted if configured as bi-directional.

This indicates the processor temperature has met or exceeded the factory calibrated

trip temperature and it will take action to reduce the temperature.

Upon activation of the TCC, the processor will stop the core clocks, reduce the core

ratio multiplier by 1 ratio and restart the clocks. All processor activity stops during this

frequency transition that occurs within 2 us. Once the clocks have been restarted at

the new lower frequency, processor activity resumes while the core voltage is reduced

by the internal voltage regulator. Running the processor at the lower frequency and

voltage will reduce power consumption and should allow the processor to cool off. If

after 1 ms the processor is still too hot (the temperature has not dropped below the

TCC activation point, DTS still = 0 and PROCHOT is still active), then a second

frequency and voltage transition will take place. This sequence of temperature

checking and frequency and voltage reduction will continue until either the minimum

frequency has been reached or the processor temperature has dropped below the TCC

activation point.

If the processor temperature remains above the TCC activation point even after the

minimum frequency has been reached, then clock modulation (described below) at

that minimum frequency will be initiated.

There is no end user software or hardware mechanism to initiate this automated TCC

activation behavior.

A small amount of hysteresis has been included to prevent rapid active/inactive

transitions of the TCC when the processor temperature is near the TCC activation

temperature. Once the temperature has dropped below the trip temperature and the

hysteresis timer has expired, the operating frequency and voltage transition back to

the normal system operating point using the intermediate VID/frequency points.

Transition of the VID code will occur first, to insure proper operation as the frequency

is increased.

Clock modulation is a second method of thermal control available to the processor.

Clock modulation is performed by rapidly turning the clocks off and on at a duty cycle

that should reduce power dissipation by about 50% (typically a 30–50% duty cycle).

Clocks often will not be off for more than 32 microseconds when the TCC is active.

Cycle times are independent of processor frequency. The duty cycle for the TCC, when

activated by the Thermal Monitor, is factory configured and cannot be modified.

It is possible for software to initiate clock modulation with configurable duty cycles.

A small amount of hysteresis has been included to prevent rapid active/inactive

transitions of the TCC when the processor temperature is near its maximum operating

temperature. Once the temperature has dropped below the maximum operating

temperature and the hysteresis timer has expired, the TCC goes inactive and clock

modulation ceases.

Desktop 4th Generation Intel

®

 Core

™

 Processor Family, Desktop Intel

®

 Pentium

®

 Processor Family, and Desktop Intel

®

 Celeron

®

Processor Family

July 2014

Datasheet – Volume 1 of 2

Order No.: 328897-009

79