w83627hf-pw Winbond Electronics Corp America, w83627hf-pw Datasheet - Page 41

• Manufacturer Part Number: w83627hf-pw
• Description: W83627hf/f W83627hg/g Winbond Lpc I/o
• Manufacturer: Winbond Electronics Corp America

7.4.2
The W83627HF provides 2 sets for fan PWM speed control. The duty cycle of PWM can be pro-
grammed 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 repre-
sented as follows.
The PWM clock frequency also can be program and defined in the Bank0.CR5C. The application cir-
cuit is shown as follows.
Fan speed control
PWM Clock Input
Duty cycle
−
(%)
=
G
Programmed 8 - bit Register Value
D
S
R1
NMOS
Figure. 8.5
- 37 -
+12V
R2
255
W83627HF/ F/ HG/ G
Publication Release Date: June 09, 2006
+
-
PNP Transistor
C
×
100%
FAN
Revision 2.27