emc2104 Standard Microsystems Corp., emc2104 Datasheet - Page 77

• Manufacturer Part Number: emc2104
• Description: Emc2104 Dual Rpm-based Pwm Fan Controller With Hardware Thermal Shutdown
• Manufacturer: Standard Microsystems Corp.

ADDR
53h
54h
55h
74h
75h
76h
77h
78h
79h
...
Dual RPM-Based PWM Fan Controller with Hardware Thermal Shutdown
Datasheet
SMSC EMC2104
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
...
LUT 1 Temp
LUT 1 Temp
LUT 1 Temp
LUT 1 Temp
LUT 1 Temp
LUT 1 VIN2
LUT 1 Drive
LUT 1 VIN1
LUT 1 VIN2
REGISTER
3 Setting 1
4 Setting 1
3 Setting 8
4 Setting 8
LUT 1 Ext
LUT 1 Ext
LUT 1 Ext
Hysteresis
Voltage 3
Voltage 3
Setting 1
Setting 1
Setting 1
Setting 8
Setting 8
Setting 8
Setting 8
Setting 8
Setting 8
Diode 2
Diode 1
Diode 2
The Look Up Table 1 Registers hold the 40 entries of the Look Up Table that controls the drive of Fan
1. As the temperature (or voltage) channels are updated, the measured value for each channel is
compared against the respective entries in the Look Up Table and the associated drive setting is
loaded into an internal shadow register and stored.
The bit weighting for temperature inputs represents °C and is compared against the measured data.
Note that the LUT entry does not include a sign bit. The Look Up Table does not support negative
temperature values and the MSBit should not be set for a temperature input.
The bit weighting for voltage inputs represents mV above 0V and is compared against the measured
data.
LUT 1
LUT 1
...
TACH /
DRIVE
‘0’
‘1’
...
X
X
X
X
X
X
X
X
X
X
X
X
X
Table 6.50 Look Up Table 1 Registers (continued)
752.9
752.9
752.9
752.9
752.9
4096
128
B7
...
-
-
-
-
-
-
-
-
DATASHEET
376.5
376.5
376.5
376.5
376.5
2048
B6
64
64
64
64
64
64
64
64
...
-
77
188.2
188.2
188.2
188.2
188.2
1024
B5
32
32
32
32
32
32
32
32
...
-
94.12
94.12
94.12
94.12
94.12
512
B4
16
16
16
16
16
16
16
16
16
...
47.06
47.06
47.06
47.06
47.06
256
B3
...
8
8
8
8
8
8
8
8
8
23.53
23.53
23.53
23.53
23.53
128
B2
...
4
4
4
4
4
4
4
4
4
Revision 1.74 (05-08-08)
11.76
11.76
11.76
11.76
11.76
B1
64
...
2
2
2
2
2
2
2
2
2
5.88
5.88
5.88
5.88
5.88
B0
32
...
1
1
1
1
1
1
1
1
1
DEFAULT
(127°C)
(127°C)
(127°C)
(127°C)
(127°C)
(127°C)
(127°C)
(0.4V)
(0.4V)
(0.4V)
(0.4V)
(0.4V)
7Fh
7Fh
7Fh
7Fh
7Fh
92h
7Fh
7Fh
7Fh
7Fh
7Fh
7Fh
7Fh
0Ah
.. .