Dual RPM-Based PWM Fan Controller with Hardware Thermal Shutdown
Datasheet
Table 6.1 EMC2104 Register Set (continued)
REGISTER
NAME
DEFAULT
VALUE
ADDR
R/W
FUNCTION
LOCK
PAGE
Fan 2 Control Registers
Always displays the most recent fan
driver input setting for Fan 2. If the RPM
based Fan Speed Control Algorithm is
disabled, allows direct user control of
the fan driver.
80h
R/W
Fan 2 Setting
PWM2 Divide
00h
No
Page 64
Stores the divide ratio to set the
frequency for Fan 2
81h
82h
83h
85h
R/W
R/W
R/W
R/W
01h
2Bh
38h
2Ah
No
No
Page 64
Page 65
Page 67
Page 69
Sets configuration values for the RPM
based Fan Speed Control Algorithm for
Fan 2
Fan 2
Configuration1
Fan 2
Configuration 2
Sets additional configuration values for
the Fan 2 driver
SWL
SWL
Holds the gain terms used by the RPM
based Fan Speed Control Algorithm for
Fan 2
Gain 2
Fan 2 Spin Up
Configuration
Sets the configuration values for Spin
Up Routine of the Fan 2 driver
86h
87h
88h
R/W
R/W
R/W
19h
10h
SWL
SWL
SWL
Page 69
Page 71
Page 72
Sets the maximum change per update
for Fan 2
Fan 2 Step
Fan 2 Minimum
Drive
Sets the minimum drive value for the
Fan 2 driver
66h
(40%)
Holds the minimum tachometer reading
that indicates the fan is spinning
properly
Fan 2 Valid TACH
Count
89h
R/W
F5h
SWL
Page 72
Page 73
Fan 2 Drive Fail
Band Low Byte
Stores the number of Tach counts used
to determine how the actual fan speed
must match the target fan speed at full
scale drive
8Ah
8Bh
8Ch
8Dh
8Eh
8Fh
R/W
R/W
R/W
R/W
R
00h
00h
F8h
FFh
FFh
F8h
SWL
SWL
No
Fan 2 Drive Fail
Band High Byte
TACH 2 Target
Low Byte
Holds the target tachometer setting low
byte for Fan 2
Page 73
Page 73
Page 74
Page 74
TACH 2 Target
High Byte
Holds the target tachometer setting high
byte for Fan 2
No
TACH 2 Reading
High Byte
Holds the tachometer reading high byte
for Fan 2
No
TACH 2 Reading
Low Byte
Holds the tachometer reading low byte
for Fan 2
R
No
Look Up Table 2 (LUT2)
LUT 2
Configuration
Stores and controls the configuration for
LUT 2
90h
91h
R/W
R/W
00h
No
Page 75
Page 78
Stores the lowest programmed drive
setting for LUT 2
LUT
Lock 2
LUT 2 Drive 1
FBh
SMSC EMC2104
Revision 1.74 (05-08-08)
DATA4S5HEET
SMSC [ SMSC CORPORATION ]
