EMC2102 Standard Microsystems Corporation, EMC2102 Datasheet - Page 40

• Manufacturer Part Number: EMC2102
• Description: Rpm-based Fan Controller with HW Thermal Shutdown
• Manufacturer: Standard Microsystems Corporation

Revision 1.95 (10-19-06)
6.11
6.12
41h
42h
43h
51h
ADDRESS
ADDRESS
The EMC2102 contains high limits for all temperature channels.If any particular temperature channel
exceeds the high limit then the appropriate status bit is set.
Each temperature channel software limit can be individually enabled to assert the SYS_SHDN# pin if
the temperature exceeds this limit.
All Temperature Limit Registers are Software Locked.
The Fan Driver Setting Register always displays the current setting of the High Side Fan Driver. If the
RPM based Fan Control Algorithm is disabled, this register can be written to manually control the fan
driver (manual mode). See
If this register is written to while the RPM based Fan Control Algorithm is active, it will not affect the
current output drive. The value that is written will be retained however and used as the current drive
if the RPM based Fan Control algorithm is disabled.
Reading from this register will report the current fan speed setting regardless of the operating mode.
Therefore it is possible that reading from this register will not report data that was previously written
into this register.
The contents of the register represent the weighting of each bit in determining the final output voltage.
The output voltage is given by
Temperature Limit Registers
Fan Driver Setting Register
External Diode
1 High Limit
External Diode
2 High Limit
External Diode
3 High Limit
REGISTER
Fan Driver
Setting
REGISTER
FAN_OUT
Sign
Sign
Sign
B7
128
Table 6.15 Temperature Limit Registers
Table 6.16 Fan Driver Setting Register
B7
Section
=
64
64
64
B6
64
Equation
⎛
⎝
B6
VALUE
-------------------- -
255
DATASHEET
5.2.
32
32
32
32
B5
B5
⎞
⎠
[2].
×
40
VDD_5V
16
16
16
16
B4
B4
RPM-Based Fan Controller with HW Thermal Shutdown
8
8
8
8
B3
B3
4
4
4
4
B2
B2
2
B1
2
2
2
B1
1
[2]
B0
1
1
1
B0
SMSC EMC2102
00h
DEFAULT
55h
(+85°C)
55h
(+85°C)
55h
(+85°C)
DEFAULT
Datasheet