Dual RPM-Based PWM Fan Controller with Hardware Thermal Shutdown
Datasheet
Table B.9 Fan Speed Control Table Example #3 (continued)
EXTERNAL
DIODE 2
TEMPERATURE
FAN
SPEED
STEP #
EXTERNALDIODE
1 TEMPERATURE
(CPU)
PUSHED
TEMPERATURE
SETTING (DTS1)
PUSHED
TEMPERATURE
SETTING (DTS2)
TACH
TARGET
(GPU)
09h
(6826 RPM)
7
8
90oC
105oC
110oC
80oC
85oC
80oC
08h
(7680 RPM)
100oC
100oC
Note: The values shown in Table B.9 are example settings. All the cells in the look-up table are
programmable via SMBus.
Table B.10 Fan Speed Determination for Example #3 (using settings in Table B.9)
EXTERNAL
DIODE 1
TEMPERATURE
EXTERNAL
DIODE 2
TEMPERATURE
PUSHED
TEMPERATURE
(DTS1)
PUSHED
TEMPERATURE
(DTS2)
FAN DRIVE
SETTING RESULT
(CPU)
(GPU)
0Ch (5120 RPM) -
CPU requires highest
target
35°C
50°C
Example 1:
Example 2:
75°C
90°C
75°C
(translated as 65°C) (translated as 50°C)
15°C
20°C
08h (7680 RPM) -
DTS1 requires
highest target
75°C
(translated as
(translated as 80°C)
85°C)
5°C
09h (6826 RPM) -
DTS2 requires
highest target
30°C
Example 3:
75°C
97.25°C
(translated as
(translated as 70°C)
95°C)
Revision 1.74 (05-08-08)
SMSC EMC2104
DATA9S6HEET
SMSC [ SMSC CORPORATION ]
