AMD Athlon 27493 - Manual (Page 95)

Appendix A - Thermal Diode Calculations 83
26237C—May 2003 AMD Athlon™ XP Processor Model 10 Data Sheet
Preliminary Information
The formulas in Equation (3) and Equation (4) can be used to
calculate the temperature offset for temperature sensors that
do not employ series resistance cancellation. The result is
added to the value measured by the temperature sensor.
Contact the vendor of the temperature sensor being used for
the value of n
f,TS
. Refer to the document, On-Die Thermal Diode
Characterization, order# 25443, for further details.
Equation (3) shows the equation for calculating the lumped
ideality factor (n
f, lumped
) in sensors that do not employ series
resistance cancellation.
Equation (4) shows the equation for calculating temperature
offset (T
offset
) in sensors that do not employ series resistance
cancellation.
Equation (5) is the temperature offset for temperature sensors
that utilize series resistance cancellation. Add the result to the
value measured by the temperature sensor. Note that the value
of n
f,TS
in Equation (5) may not equal the value used in
Equation (4).
(3)
n
f lumped ,
n
f actual ,
=
R
T
I
high
I
low
–
( ) ⋅
k
q
--- T
die spec ,
273.15
+
( )
I
high
I
low
--------
 
 
ln ⋅
----------------------------------------------------------------------
+
(4) T
of f s e t
T
die spec ,
273.15
+
( )
=
1 n f lumped ,
n
f TS ,
---------------
–  
 
⋅
(5)
T
of f s e t
T
die spec ,
273.15
+
( )
=
1
n
f actual ,
n
f TS ,
---------------
–
 
 
⋅