HPFANG Datasheet, PDF (6/9 Pages) Champion Microelectronic Corp. – HP Power Supply Fan Controller DATA SHEET

http://www.championmicro.com.tw
HPFANG+/-
HP Power Supply Fan Controller DATA SHEET
Description
Functional Description
HPFANG+/- is a Fan control with an internal VREF=5V and maximum IREF=2.5mA current sourcing ability
reference voltage/current . HPFANG+/- operates at 25KHz and the duty cycle ranges from 1.5% to 100%. It
transfers input PWMing command signal, thermal signal to fan control signal. HPFANG+/- combines thermal
signal, which is from power supply load, represented by Rthermister, and motherboard temperature signal,
represented by FANCMD, to generate fan control signal. It features high efficiency, larger variable range speed,
and low cost.
Error Amplifier Output TEAO
Error Amplifier receives power supply load information, which is represented by Rthermistor and then generates signal TEAO.
It is an internal compensated OP. It feedback resistor RF (see figure 1.) needs to be calculated respect to the chosen SPEC of
thermal resistor RTHERMISTER
Error Amplifier output TEAO is one of signals, which decides FANPWMOUT duty cycle, and finally decides the fan speed. As
power supply load increase, RTHERMISTER reduce, TEAO increae, FANPWMOUT duty increase, then the FAN speed increases.
Figure 1. FANPWMOUT Control Circuit
Rc ^R1
15K
R4
Rt _100K CN1
2
Rs ^R7
0
1
CON2
R10
0.5K
Rf ^R2
4K
R5
10
C4
0.1uF
U1 HPFANG
1 _TEAO
VREF ⁸
2
TFB
7
VCC
3
6
FANCMD FANPWMOUT
4
CAVERAGE
5
GND
HouseKeeping
R8
C1
0.01uF
R6
10
TACH
4
3
2
1
VCC
R3
10K
C3
C2
0.01uF 47uF/25V
NPN
R9
FAN1
UFan
CN2
1
2
CON2
2013/01/17 Rev. 1.2
Champion Microelectronic Corporation
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