F71872
The F71872 provides offset register for each temperature. The offset value is an 7-bit, 2’s complement
value. The reading temperature value will be the result of the offset value added to the monitored value. The
offset format is as the following table:
Offset Value
63°C
2°C
High Byte
0011 1111
0000 0010
0000 0001
0000 0000
0100 0001
0100 0010
0100 0000
1°C
0°C
-1°C
-2°C
-64°C
The F71872 can provide two external thermal sensors to detect temperature. When monitored
temperature exceeds the over-temperature threshold value, OVT# (pin77) will be asserted until the
temperature goes below the hysteresis temperature.
To
T
HYST
OVT#
6.4.3 Fan speed count
Inputs are provided by the signals from fans equipped with tachometer outputs. The level of these signals
should be set to TTL level, and maximum input voltage cannot be over VCC. If the input signals from the
tachometer outputs are over the VCC, the external trimming circuit should be added to reduce the voltage to
obtain the input specification. The normal circuit and trimming circuits are shown as follows:
18
July, 2007
V0.28P
FINTEK [ FEATURE INTEGRATION TECHNOLOGY INC. ]
