5000 datasheet(79/104 Pages) INTEL

79 / 104 page

Dual-Core Intel® Xeon® Processor 5000 Series Datasheet

Thermal Specifications

6.2.6

Tcontrol and Fan Speed Reduction

Tcontrol is a temperature specification based on a temperature reading from the

thermal diode. The value for Tcontrol will be calibrated in manufacturing and configured

for each processor. The Tcontrol value is set identically for both processor cores. The

Tcontrol temperature for a given processor can be obtained by reading the

IA32_TEMPERATURE_TARGET MSR in the processor. The Tcontrol value that is read

from the IA32_TEMPERATURE_TARGET MSR must be converted from Hexadecimal to

Decimal and added to a base value of 60

° C. The value of Tcontrol may vary from 0x00h

to 0x1Eh.

When Tdiode is above Tcontrol, then TCASE must be at or below TCASE_MAX as defined by

the thermal profile. (Refer to Figure 6-1, Figure 6-2 and Figure 6-3 ; Table 6-2,

Table 6-3, Table 6-5, Table 6-6 and Table 6-8). Otherwise, the processor temperature

can be maintained at or below Tcontrol.

6.2.7

Thermal Diode

The Dual-Core Intel Xeon Processor 5000 series incorporates an on-die PNP transistor

whose base emitter junction is used as a thermal “diode”, one per core, with its

collector shorted to Ground. A thermal sensor located on the system board may

monitor the die temperature of the processor for thermal management and fan speed

control. Table 6-9, Table 6-11 and Table 6-12 provide the “diode” parameters and

interface specifications. Two different sets of “diode” parameters are listed in Table 6-9

and Table 6-11. The Diode Model parameters (Table 6-9) apply to traditional thermal

sensors that use the Diode Equation to determine the processor temperature.

Transistor Model parameters (Table 6-11) have been added to support thermal sensors

that use the transistor equation method. The Transistor Model may provide more

accurate temperature measurements when the diode ideality factor is closer to the

maximum or minimum limits. This thermal “diode” is separate from the Thermal

Monitor’s thermal sensor and cannot be used to predict the behavior of the Thermal

Monitor.

When calculating a temperature based on thermal diode measurements, a number of

parameters must be either measured or assumed. Most devices measure the diode

ideality and assume a series resistance and ideality trim value, although some are

capable of also measuring the series resistance. Calculating the temperature is then

accomplished by using the equations listed under Table 6-9. In most temperature

sensing devices, an expected value for the diode ideality is designed-in to the

temperature calculation equation. If the designer of the temperature sensing device

assumes a perfect diode, the ideality value (also called ntrim) will be 1.000. Given that

most diodes are not perfect, the designers usually select an ntrim value that more

closely matches the behavior of the diodes in the processor. If the processors diode

ideality deviates from that of ntrim, each calculated temperature will be offset by a fixed

amount. The temperature offset can be calculated with the equation:

Terror(nf) = Tmeasured X (1- nactual/ntrim )

where Terror(nf) is the offset in degrees C, Tmeasured is in Kelvin, nactual is the measured

ideality of the diode, and ntrim is the diode ideality assumed by the temperature sensing

device.

In order to improve the accuracy of diode based temperature measurements, a new

which will contain thermal diode characterization data. During manufacturing each

processor’s thermal diode will be evaluated for its behavior relative to a theoretical

diode. Using the equation above, the temperature error created by the difference

5000 датащи(PDF) 79 Page - Intel Corporation

5000 датащи(HTML) 79 Page - Intel Corporation

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

датащи скачать

ссылки URL