SMBus Fan Control with 1°C Accurate Temperature Monitoring
Datasheet
‘1’ - The ALERT / TACH pin will function as a high impedance TACH input. This may require an
external pull-up resistor to set the proper signaling levels.
Bit 1 - TCRITOVRD - Allows the TCRIT limit to be overridden.
'0' (default) - TCRIT limit is set to default value and locked.
'1' - The TCRIT limit is unlocked for modification. The TCRIT limit can only be changed once. To
adjust TCRIT again, a power cycle is required.
Bit 0 - QUEUE - Sets the number of external diode over-temp measurements required to assert ALERT
/ TACH pin.
'0' (default) - ALERT / TACH pin is asserted (and status bit set) after one external temperature
measurement exceeds the high limit or the TCRIT limit or drops below the low limit.
'1' - ALERT / TACH pin is asserted (and status bit set) after three consecutive external temperature
measurements exceed the high limit or the TCRIT limit or drop below the low limit.
6.6
Conversion Rate Register
Table 6.5 Conversion Rate Register
ADDR.
R/W
REGISTER
B7
B6
B5
B4
B3
B2
B1
B0
DEFAULT
04h and
0Ah
Conversion
Rate
R/W
-
-
-
-
CONV3
CONV2
CONV1 CONV0
08h
Bits 3- 0 - CONV[3:0] - The Conversion Rate Register controls the conversion rate per Table 6.6.
Table 6.6 Conversion Rates
CONV[3:0]
3
2
1
0
CONVERSIONS PER SECOND
0
0
0
0
0
0
0
0
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
0
0
1
1
0
0
0
1
0
1
0
1
0
1
0
1
1/16
1/8
1/4
1/2
1
2
4
8
16 (default)
32
all others
32
Revision 2.53 (03-13-07)
SMSC EMC2101
DATA3S4HEET
SMSC [ SMSC CORPORATION ]
