641 datasheet(83/106 Pages) INTEL

83 / 106 page

Datasheet

Thermal Specifications and Design Considerations

processor temperature. Transistor Model parameters (Table 31) 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

Table 30.

Thermal “Diode” Parameters using Diode Model

Symbol

Parameter

Min

Typ

Max

Unit

Notes

IFW

Forward Bias Current

—

200

µA

NOTES:

1. Intel does not support or recommend operation of the thermal diode under reverse bias.

Diode Ideality Factor

1.000

1.009

1.050

2, 3, 4

2. Characterized across a temperature range of 50 – 80 °C.

3. Not 100% tested. Specified by design characterization.

4. The ideality factor, n, represents the deviation from ideal diode behavior as exemplified by the diode equation:

IFW = IS * (e

qVD/nkT –1)

where IS = saturation current, q = electronic charge, VD = voltage across the diode, k = Boltzmann Constant,

and T = absolute temperature (Kelvin).

Series Resistance

2.79

4.52

6.24

Ω

2, 3, 5

5. The series resistance, RT, is provided to allow for a more accurate measurement of the junction temperature.

RT, as defined, includes the lands of the processor but does not include any socket resistance or board trace

resistance between the socket and the external remote diode thermal sensor. RT can be used by remote diode

thermal sensors with automatic series resistance cancellation to calibrate out this error term. Another

application is that a temperature offset can be manually calculated and programmed into an offset register in

the remote diode thermal sensors as exemplified by the equation:

Terror = [RT * (N-1) * IFWmin] / [nk/q * ln N]

where Terror = sensor temperature error, N = sensor current ratio, k = Boltzmann Constant, q = electronic

charge.

Table 31.

Thermal “Diode” Parameters using Transistor Model

Symbol

Parameter

Min

Typ

Max

Unit

Notes

IFW

Forward Bias Current

—

200

µA

1, 2

NOTES:

1. Intel does not support or recommend operation of the thermal diode under reverse bias.

Same as IFW in Table 30.

Emitter Current

—

200

µA

Transistor Ideality

0.997

1.001

1.005

—

3, 4, 5

3. Characterized across a temperature range of 50 – 80 °C.

4. Not 100% tested. Specified by design characterization.

5. The ideality factor, nQ, represents the deviation from ideal transistor model behavior as exemplified by the

equation for the collector current:

IC = IS * (e

qVBE/nQkT –1)

Where IS = saturation current, q = electronic charge, VBE = voltage across the transistor base emitter junction

(same nodes as VD), k = Boltzmann Constant, and T = absolute temperature (Kelvin).

Beta

0.391

—

0.760

—

3, 4

Series Resistance

2.79

4.52

6.24

Ω

3, 6

6. The series resistance, RT, provided in the Diode Model Table (Table 30) can be used for more accurate readings

as needed.

641 Datasheet(PDF) 83 Page - Intel Corporation

641 Datasheet(HTML) 83 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

Datasheet Download

Link URL