1 sample preparation, Sample preparation – Intel CELERON 200 User Manual
Page 33
Thermal Metrology
Thermal and Mechanical Design Guidelines
33
3.3.1
Sample Preparation
In order to accurately measure the processor power consumption, it is required to
attach sense resistor and replace one of the motherboard resistors. Schematic
diagram in Figure 13 illustrates the precision resistor (R
SENSE
) attached in series with
processor circuitry. The processor power consumption can be estimated by
Equation 5 P
D
= V
CC
× (V
i
/ R
SENSE
)
Where:
P
D
= Processor total power dissipation (W) (assumes all power dissipates
through the processor die)
V
CC
= Processor core voltage.
V
i
= Voltage measured across precision sense resistor.
R
SENSE
= Given resistance value of precision resistor.
The Isotek 4 terminal (Kelvin) precision resistor (with resistance of 1 mΩ and
Tol=0.1%) is recommended to be used for processor power measurement. Locate the
inductor L1VR inductor (near processor) on motherboard and attach the Isotek
precision resistor in-series with inductor as illustrated in Figure 13 schematic and
Figure 14 board layout schematic diagram. Additionally, it is required to replace
R27VR chip resistor (near processor) with a 19.6 KΩ rated chip resistor as illustrated
in Figure 15. The Walsin chip resistor (WR06X1962FTL) is one of the recommended
chip resistors for the rework.
Table 4. Test Accessories
5.
Description
Q
uantity
7.
Part Number
N
otes
9. Isotek 4 terminal
(Kelvin) precision
resistor
10. 1 11. P/N A-N-R001-F1-K2-0.1.
R=1 mΩ, Tol=0.1%, P=2W,
TCR<10 ppm/°C
12.
13. Walsin chip
resistor
14. 1 15. WR06X1962FTL. R= 19.6 KΩ,
Tol =1%, P=0.1W, TCR<200
ppm/°C.
16.
NOTE:
1.
2.