w83l786nr Winbond Electronics Corp America, w83l786nr Datasheet - Page 19

• Manufacturer Part Number: w83l786nr
• Description: W83l786nr W83l786ng Winbond H/w Monitoring Ic
• Manufacturer: Winbond Electronics Corp America

7.6.2
The W83L786NR/NG provides two sets for PWM/DC fan speed control. The duty cycle of PWM or the
output voltage of DC can be programmed by a 4-bit register. There are four mode to control fan speed
which are set by programming CR80 [3:2] and CR [5:4], and default are FAN_SET mode.
7.6.2.1. Default Fan Speed Setting
There is a pin to set the default value for fan speed control by adjusting external serial resistors. After
power up, the default value will be stored in CR90 (FAN_SET mode). The figure and table are shown
below.
7.6.2.2. PWM Mode
SECTION
Fan Speed Control
3
2
1
0
V C C
Duty
−
cycle
(%)
=
FAN SPEED RATE
Figure 8 OFFSET Setting
Programmed
R b
R a
100﹪
81﹪
62﹪
43﹪
- 14 -
- 4
W83L786NR/ W83L786NG
16
bit
Register
F A N _ S E T
Value
9.1K
4.7K
9.1K
×
RA
×
100
%
9.1K
4.7K
9.1K
RB
×