f75386 Feature Integration Technology Inc., f75386 Datasheet - Page 19
f75386
Manufacturer Part Number
f75386
Description
Dual ?1o C Accuracy Temperature Sensor Ic With Fan Speed Control
Manufacturer
Feature Integration Technology Inc.
Datasheet
1.F75386.pdf
(28 pages)
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