W83627F Information Storage Devices, Inc, W83627F Datasheet - Page 37

• Manufacturer Part Number: W83627F
• Description: LPC Interface I/o Plus Kbc, Game Port, Midi Port
• Manufacturer: Information Storage Devices, Inc

The W83627HF provides 2 sets for fan PWM speed control. The duty cycle of PWM can be programmed
by a 8-bit registers which are defined in the Bank0 CR5A and CR5B. The default duty cycle is set to
100%, that is, the default 8-bit registers is set to FFh. The expression of duty can be represented as
follows.
The PWM clock frequency also can be program and defined in the Bank0.CR5C . The application circuit
is shown as follows.
2.5 SMI# interrupt mode
2.5.1 Voltage SMI# mode :
SMI# interrupt for voltage is Two-Times Interrupt Mode. Voltage exceeding high limit or going below
low limit will causes an interrupt if the previous interrupt has been reset by reading all the interrupt
Status Register. (Figure 2.6 )
Duty
cycle
PWM Clock Input
( % )
Programmed 8 - bit Register Value
G
D
S
Figure 2.5
R1
NMOS
- 33 -
+12V
R2
255
+
-
Publication Release Date:November 2002
PNP Transistor
C
FAN
W83627HF/F
100%
Revision 2.0