Fan Control Device with High Frequency PWM and Temperature Monitors
Datasheet
Temperature Reading registers will be updated automatically by the EMC2300 Chip with a minimum
frequency of 4Hz.
Note: These registers are read only – a write to these registers has no effect.
Each of the temperature reading registers are mapped to a zone. Each PWM may be programmed to
operate in the auto fan control operating mode by associating a PWM with one or more zones. The
following is a list of the zone associations.
Zone 1 is controlled by Remote Diode 1 Temp Reading
Zone 2 is controlled by Internal Temp Reading (Ambient Temperature Sensor)
Zone 3 is controlled by Remote Diode 2 Temp Reading
Table 8.5 Temperature vs. Register Reading
TEMPERATURE
READING (DEC)
READING (HEX)
-127°c
-127
81h
.
.
.
.
.
.
.
.
.
-50°c
-50
CEh
.
.
.
.
.
.
.
.
.
0°c
0
00h
.
.
.
.
.
.
.
.
.
50°c
50
32h
.
.
.
.
.
.
.
.
.
127°c
127
7Fh
80h
(SENSOR ERROR)
8.2.3
Registers 28-2Fh: Fan Tachometer Reading
Table 8.6 Registers 28-2Fh: Fan Tachometer Reading
Register
Address
Read/
Write
Bit 7
(MSb)
Bit 0
(LSb)
Default
Value
Register Name
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
28h
R
R
R
R
R
R
R
R
Tach1 LSB
Tach1 MSB
Tach2 LSB
Tach2 MSB
Tach3 LSB
Tach3 MSB
Tach4 LSB
Tach4 MSB
7
15
7
6
14
6
5
13
5
4
12
4
3
11
3
2
10
2
1
9
1
9
1
9
1
9
0
8
0
8
0
8
0
8
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
29h
2Ah
2Bh
15
7
14
6
13
5
12
4
11
3
10
2
2Ch
2Dh
2Eh
15
7
14
6
13
5
12
4
11
3
10
2
2Fh
15
14
13
12
11
10
Revision 0.2 (06-14-06)
SMSC EMC2300
DATA5S0HEET
SMSC [ SMSC CORPORATION ]
