Intel 4 HT 631 80552PG0802M2M Data Sheet

Datasheet

83

 

processor temperature. Transistor Model parameters (

) 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 

I

FW

Forward Bias Current

5

—

200

µA

1

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

n

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:

I

FW

 = I

S

 * (e 

qV

D

/nkT

 –1)

 

where I

S

 = saturation current, q = electronic charge, V

D

 = voltage across the diode, k = Boltzmann Constant, 

and T = absolute temperature (Kelvin).

R

T

Series Resistance

2.79

4.52

6.24

Ω

, 

, 5

5. The series resistance, R

T

, is provided to allow for a more accurate measurement of the junction temperature. 

R

T

, 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. R

T

 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:

T

error

 = [R

T

 * (N-1) * I

FWmin

] / [nk/q * ln N]

 

where T

error

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

charge. 

I

FW

Forward Bias Current

5

—

200

µA

1,  2

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

2.

Same as I

FW 

I

E

Emitter Current

5

—

200

µA

n

Q

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:

I

C

 = I

S

 * (e 

qV

BE

/n

Q

kT

 –1)

 

Where I

S

 = saturation current, q = electronic charge, V

BE

 = voltage across the transistor base emitter junction 

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

Beta

0.391

—

0.760

—

, 

R

T

Series Resistance

2.79

4.52

6.24

Ω

, 6

6. The series resistance, R

T,

 provided in the Diode Model Table (

) can be used for more accurate readings 

as needed.