Thermal Specifications
Table 6-10. Thermal Diode Interface
Land Name
Land Number
Description
THERMDA
AL1
AK1
AJ7
diode anode
diode cathode
diode anode
diode cathode
THERMDC
THERMDA2
THERMDC2
AH7
.
Table 6-11. Thermal Diode Parameters using Transistor Model
Symbol
Parameter
Min
Typ
Max
Unit
Notes
I
Forward Bias Current
Emitter Current
Transistor Ideality
-
5
-
-
200
200
µA
µA
-
1, 2
FW
I
5
E
n
0.997
0.391
2.79
1.001
-
1.005
0.760
6.24
3, 4, 5
3, 4
Q
Beta
-
R
Series Resistance
4.52
3, 6
T
Ω
Notes:
1.
2.
3.
4.
5.
Intel does not support or recommend operation of the thermal diode under reverse bias.
Same as I in the diode model in Table 6-9.
Characterized across a temperature range of 50-80°C.
Not 100% tested. Specified by design characterization.
The ideality factor, n , represents the deviation from ideal transistor model behavior as exemplified by the
equation for the collector current: I = I * (e
FW
Q
qVBE/n kT
- 1)
BE
C
S
Q
Where I = saturation current, q = electronic charge, V = voltage across the transistor based emitter
S
junction (same nodes as V ), k = Boltzmann Constant, and T = absolute temperature (Kelvin).
The series resistance, R provided in Table 6-9 can be used for more accurate readings as needed.
D
6.
T
Table 6-12. Parameters for Tdiode Correction Factor
Symbol
Parameter
Typ
Unit
Notes
n
Diode Ideality used to calculate
Tdiode_Offset
1.008
1
trim
Tdiode_Base
0
°C
1
Notes:
1.
®
®
See the Dual-Core Intel Xeon Processor 5000 Series Thermal/Mechanical Design Guidelines for more
information on how to use the Tdiode_Offset, Tdiode_Base and n
parameters for fan speed control.
trim
§
Dual-Core Intel® Xeon® Processor 5000 Series Datasheet
81