emc2105 Standard Microsystems Corp., emc2105 Datasheet - Page 85

• Manufacturer Part Number: emc2105
• Description: Emc2105 Rpm-based High Side Fan Controller With Hardware Thermal Shutdown
• Manufacturer: Standard Microsystems Corp.

ADDR
42h
46h
50h
RPM-Based High Side Fan Controller with Hardware Thermal Shutdown
Datasheet
SMSC EMC2105
B.3
STEP #
SPEED
FAN
1
2
3
4
5
6
Configuration
Configuration
Configuration
REGISTER
Fan 1 Spin
LUT 1
Fan 1
EXTERNAL DIODE
Up
1 TEMPERATURE
1
Example #3
This example uses the RPM based Fan Speed Control Algorithm. The Spin Level (used by the Spin
Up Routine) should be changed to 50% drive for a total Spin Time of 1 second. For all other RPM
configuration settings, the default conditions are used.
For control inputs, it uses the External Diode 1 channel normally, the External Diode 2 channel
normally, and both Pushed Temperature registers in DTS format. The configuration is set as shown in
Table B.8
Note that when using DTS data, the USE_DTS_F1 and / or USE_DTS_F2 bits should be set. The
Pushed Temperature Registers are loaded with the normal DTS values as received by the processor.
When the DTS value is used by the Look Up Table, the value that is stored in the Pushed Temperature
Register is subtracted from a fixed temperature of 100°C. This resultant value is then compared
against the Look Up Table thresholds normally. When programming the Look Up Table, it is necessary
to take this translation into account else incorrect settings may be selected.
(CPU)
35
40
50
60
70
80
o
o
o
o
o
o
C
C
C
C
C
C
DRIVE_FAIL_CNT
USE_D
while
TS_F1
ALGO
EN_
B7
1
0
1
1 [1:0]
Table B.9
Table B.8 Look Up Table Example #3 Configuration
Table B.9 Fan Speed Control Table Example #3
TEMPERATURE
USE_D
TS_F2
EXTERNAL
B6
1
0
1
DIODE 2
RANGE[1:0]
(GPU)
100
shows how the table is loaded.
65
75
85
90
95
o
o
o
o
o
o
C
C
C
C
C
C
NOKICK
LUT_LO
CK
B5
DATASHEET
0
1
0
1
SETTING (DTS1)
TEMPERATURE
85
TACH /
DRIVE
PUSHED
B4
EDGES[1:0]
0
0
0
50
55
60
65
70
75
SPIN_LVL[2:0]
o
o
o
o
o
o
C
C
C
C
C
C
TEMP3_CFG
B3
1
1
1
[1:0]
SETTING (DTS2)
TEMPERATURE
B2
0
0
0
PUSHED
40
45
50
55
60
65
UPDATE[2:0]
o
o
o
o
o
o
C
C
C
C
C
C
SPINUP_TIME
TEMP4_CFG
B1
1
1
1
Revision 1.74 (05-08-08)
[1:0]
[1:0]
B0
1
0
0
(1007 RPM)
(2048 RPM)
(3072 RPM)
(4096 RPM)
(5120 RPM)
(6144 RPM)
TARGET
TACH
3Dh
1Eh
0Ch
0Ah
14h
0Fh
SETTING
CBh
EAh
0Ah