emc2104 Standard Microsystems Corp., emc2104 Datasheet - Page 69

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

ADDR
ADDR
Dual RPM-Based PWM Fan Controller with Hardware Thermal Shutdown
Datasheet
45h
85h
SMSC EMC2104
46h
86h
6.24
6.25
R/W
R/W
R/W
R/W
R/W
R/W
GAIND OR GAINP OR GAINI [1:0]
The Gain Register stores the gain terms used by the proportional and integral portions of each of the
RPM based Fan Speed Control Algorithms. These gain terms are used as the KD, KI, and KP gain
terms in a classic PID control solution.
1
0
0
1
1
The Fan Spin Up Configuration Register controls the settings of Spin Up Routine. The Fan Spin Up
Configuration Register is software locked.
Bit 7 - 6 - DRIVE_FAIL_CNTx[1:0] - Determines how many update cycles are used for the Drive Fail
detection function as shown in
the desired tach target.
Gain Registers
Fan Spin Up Configuration Registers
Fan 1 Spin Up
Fan 2 Spin up
REGISTER
Configuration
Configuration
REGISTER
Register
Register
Gain 1
Gain 2
Table 6.37 Fan Spin Up Configuration Registers
DRIVE_FAIL
DRIVE_FAIL
_CNT1 [1:0]
_CNT2 [1:0]
B7
B7
-
-
0
0
1
0
1
Table 6.35 Gain Registers
Table 6.36 Gain Decode
Table
B6
B6
DATASHEET
-
-
6.38. This circuitry determines whether the fan can be driven to
ICK1
ICK2
NOK
NOK
B5
69
B5
GAIND[1:0]
GAIND[1:0]
B4
B4
SPIN_LVL[2:0]
SPIN_LVL[2:0]
RESPECTIVE GAIN FACTOR
B3
B3
GAINI[1:0]
GAINI[1:0]
4x (default)
B2
B2
1x
2x
8x
SPINUP_TIM
SPINUP_TIM
B1
GAINP[1:0]
GAINP[1:0]
B1
E [1:0]
E [1:0]
Revision 1.74 (05-08-08)
B0
B0
DEFAULT
DEFAULT
2Ah
2Ah
0Dh
0Dh