W83697HF Datasheet, PDF (99/167 Pages) Winbond – WINBOND I/O

W83697HF/F
9.4.2 Fan speed control
The W83697HF 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.
Duty − c y c l e( % ) = ^{Programmed 8 - bit Registe r V a l u e} × 1 0 0 %
255
The PWM clock frequency also can be program and defined in the Bank0.CR5C . The application circuit
is shown as follows.
Figure 9.5
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Publication Release Date: Feb. 2002
Revision 0.70