f75375 Feature Integration Technology Inc., f75375 Datasheet - Page 14
f75375
Manufacturer Part Number
f75375
Description
Fintek Hardware Monitor Ic Datasheet
Manufacturer
Feature Integration Technology Inc.
Datasheet
1.F75375.pdf
(55 pages)
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Part Number:
f75375SG
Manufacturer:
FINTEK
Quantity:
20 000
6.3.1
The F75375S provides 2 fan speed control methods:
The range of DC output is 0~3.3V, controlled by 8-bit register (CR76 for FAN1 and CR86 for FAN2). 1 LSB is about 0.013V.
The output DC voltage is amplified by external OP circuit, thus to reach maximum FAN OPERATION VOLTAGE, 12V.
The output voltage will be given as followed:
Determine the fan counter according to:
In other words, the fan speed counter has been read from register, the fan speed can be evaluated by the following equation.
As for fan, it would be best to use 2 pulses tachmeter output per round.
6.3.1.1 Linear Fan Control
Fintek
Fan speed control
Figure 5-5 Fan with Tach Pull-Up to +12V, or Totern-Pole
Figure 5-7. Fan with Tach Pull-Up to +5V, or Totern-Pole
FAN Out
FAN Out
+5V
GND
+12V
GND
+5V
+12V
Output and Register Attenuator
Output and Register Attenuator
Pull-up resister
4.7K Ohms
Pull-up resister
4.7K Ohms
1K~2.7K
22K~30K
Fan Input
Fan Input
10K
10K
FANIN1
F75375S
FANIN 1
F75375S
Count
RPM
1. LINEAR FAN CONTROL
8
=
=
1 ×
1 ×
5 .
Count
5 .
Connector
RPM
Connector
Feature Integration Technology Inc.
FAN
Figure 5-6 Fan with Tach Pull-Up to +12V, or
FAN
.Figure 5-8 Fan with Tach Pull-Up to +5V, or
10
10
FAN Out
FAN Out
6
+12V
GND
6
+5V
GND
+12V
+5V
Totem-Pole Putput and Zener Clamp
Totem-Pole Putput and Zener Clamp
F75375S/F75375SG
Pull-up resister < 1K
or totem-pole output
2. PWM DUTY CYCLE
Pull-up resister < 1K
or totem-pole output
3.3V Zener
3.3V Zener
> 1K
> 1K
Fan Input
Fan Input
FANIN 1
F75375S
FANIN1
F75375S
July 2007
V0.26P