F81866A Datasheet, PDF (44/210 Pages) Feature Integration Technology Inc. – 6 UARTs Super IO With 128 Bytes FIFO and Power

Temp.
TFan1
T1
Ta
F81866A
Tb
TFan1
Time
1. Ctup, Ctdn Can be Programmed to 1, ½, ¼, 0
2. Ta Can be Selected to the Same Temp. Source (Ex:T1)
TFan1= T1 + (Ta-Tb)*Ctup ; TFan1= T1 + (Ta-Tb)*Ctdn
Figure 6-14
In application, we can set the Ta as the 2^nd sensor temperature and Tb as the temperature which
starts the scaling. So if the 2^nd sensor temperature Ta is higher or lower than Tb, the fan1 speed
would be changed with it.
EX: Ta = T1, Tb = 60, Ctu = 1, Ctd = 1/4
Figure 6-15
44
Jan, 2012
V0. 12P