EMC6D100-DK SMSC [SMSC Corporation], EMC6D100-DK Datasheet - Page 53

• Manufacturer Part Number: EMC6D100-DK
• Description: ENVIRONMENTAL MONITORING AND CONTROL DEVICE WITH AUTOMATIC FAN CAPABILITY
• Manufacturer: SMSC [SMSC Corporation]

Environmental Monitoring and Control Device
Datasheet
8.19
SMSC EMC6D100/EMC6D101
REGISTER
ADDRESS
5Fh
60h
61h
Temperature
Below Fan Temp Limit: Fan is off or at Fan PWM
Registers 5F-61h: Auto Fan Speed Range, PWM Frequency
These registers become read only when the Lock bit is set. Any further attempts to write to these registers
shall have no effect.
In Auto Fan Mode, when the temperature for a zone is above the Temperature Limit (registers 67-69h) and
below the Absolute Temperature Limit (registers 6A-6Ch) the speed of a fan assigned to that zone is
determined as follows:
When the temperature reaches the Fan Temp Limit for a zone, the PWM output assigned to that zone is at
Fan PWM Minimum. Between Fan Temp Limit and (Fan Temp Limit + Range), the PWM duty cycle
increases linearly according to the temperature as shown in the figure below.
Minimum depending on bit[7:5] of register 62h
READ/
WRITE
R/W
R/W
R/W
and bit 2 of register 7Fh
Range/Frequency
Range/Frequency
Range/Frequency
REGISTER
NAME
Fan 1
Fan 2
Fan 3
FIGURE 8.1 - FAN ACTIVITY ABOVE FAN TEMP LIMIT
Table 8.7 - Fan Spin-Up Register
(MSB)
BIT 7
RAN3
RAN3
RAN3
000
001
010
011
100
101
110
111
DATASHEET
SPIN[2:0]
output at MIN FAN SPEED
Temperature LIMIT: PWM
BIT 6
RAN2
RAN2
RAN2
Page 53
0 sec
100ms
250ms
(default)
400ms
700ms
1000ms
2000ms
4000ms
BIT 5
RAN1
RAN1
RAN1
SPIN UP
TIME
BIT 4
RAN0
RAN0
RAN0
PWM Duty is linear over
BIT 3
RES
RES
RES
this range
BIT 2
FRQ2
FRQ2
FRQ2
LIMIT+ RANGE: PWM
Output at 100% Duty
BIT 1
FRQ1
FRQ1
FRQ1
(LSB)
BIT 0
FRQ0
FRQ0
FRQ0
Rev. 09-09-04
DEFAULT
VALUE
C3h
C3h
C3h