Dual RPM-Based PWM Fan Controller with Hardware Thermal Shutdown
Datasheet
Table 6.48 TEMP3_CFG Decode
TEMP3_CFG [1:0]
1
0
TEMPERATURE CHANNEL USED
0
0
0
1
External Diode 3 (default)
TRIP_SET / VIN4 Voltage
Pushed Temperature 1 (LUT1)
Pushed Temperature 3 (LUT2)
1
1
0
1
Reserved
Bits 1-0 - TEMP4_CFG[1:0] - These bits determine the temperature channel that is used for the
Temperature 4 inputs to the Look Up Table as shown in Table 6.49.
Table 6.49 TEMP4_CFG Decode
TEMP4_CFG [1:0]
1
0
TEMPERATURE CHANNEL USED
0
0
0
1
Internal Diode (default)
External Diode 4
Pushed Temperature 2 (LUT1)
Pushed Temperature 4 (LUT2)
1
1
0
1
Reserved
APPLICATION NOTE: When any of the External Diode 1, External Diode 2, and External Diode 3 channels are
configured to operate as voltage inputs, the voltage data is used in the Look Up Table instead
of the corresponding temperature data. Therefore, the threshold settings must be updated
accordingly. All voltage channels (including VIN1, VIN2, and VIN3) are assumed to be
increasing (i.e. a larger voltage reading indicates a higher fan speed).
6.33
Look Up Table 1 Registers
Table 6.50 Look Up Table 1 Registers
TACH /
DRIVE
ADDR
R/W
REGISTER
B7
B6
B5
B4
B3
B2
B1
B0
DEFAULT
‘0’
‘1’
4096
128
2048
64
1024
32
512
16
256
8
128
4
64
2
32
1
LUT 1 Drive
Setting 1
51h
R/W
FBh
LUT 1 Ext
Diode 1
Setting 1
7Fh
(127°C)
X
X
-
64
32
16
8
4
2
1
52h
R/W
LUT 1 VIN1
Setting 1
7Fh
(0.4V)
752.9
376.5
188.2
94.12
47.06
23.53
11.76
5.88
Revision 1.74 (05-08-08)
SMSC EMC2104
DATA7S6HEET
SMSC [ SMSC CORPORATION ]
