f75386 Feature Integration Technology Inc., f75386 Datasheet - Page 19

• Manufacturer Part Number: f75386
• Description: Dual ?1o C Accuracy Temperature Sensor Ic With Fan Speed Control
• Manufacturer: Feature Integration Technology Inc.

F75386
7.13 PWM Value Register  Index 4Ch
7.14 FAN PWM Frequency Register  Index 4Dh
7-6
4-3
2-0
Bit
Power on default<7:0> =00h
Power on default<7:0> =17h
7-0
5
Bit
Bit
7-5
4-0
PWM Spin-Up Duty
PWM Spin-Up Time
Fast Tachometer
Reserved
Name
Spin-up
PWM_DUTY
Cycle
PWM_FREQ
Reserved
Name
Name
Attribute
R/W
R/W
R/W
RO
Attribute
Attribute
R/W
R/W
RO
The time unit is 0.5 second. The default time is 3.5 seconds
000: No Spin-up.
001: 0.5 seconds
010: 1.0second
011: 1.5 second
100: 2.0 second
101: 2.5 second
110: 3.0 second
111: 3.5 second
These bits are not used and always set to 0.
0: The spin-up time and duty depends on bit 4-0.
1: Sets the PWMOUT to 100% until the spin-up times out or the minimum RPM limit is
reached. When this bit is set, the spin-up duty cycle is always 100%.
If PWM spin up time (bit2-0) = 000, the spin-up process is bypassed.
00: No spin-up (unless bit5 is set to 0)
01: 50%
10: 75%~81%. Depends on PWM frequency select.
11: 100%.(default)
These bits are unused and always set to 0
PWM frequency = PWM_CLK / 2n
(PWM_CLK = 333 kHz or 1.4 kHz , n = value of this register)
If PWM_MODE is set to 0, this register is read only and reflects the current PWM
duty-cycle value from the T-P lookup table.
If PWM_MODE is set to 1, this register is read/write and the software programs this
register directly.
-15-
Description
Description
Description
F75386
July,
V0.27P
2007