FAN7930C Fairchild Semiconductor, FAN7930C Datasheet - Page 18

• Manufacturer Part Number: FAN7930C
• Description: The FAN7930C is an active power factor correction (PFC) controller for boost PFC applications that operate in critical conduction mode (CRM)
• Manufacturer: Fairchild Semiconductor

© 2010 Fairchild Semiconductor Corporation
FAN7930C • Rev. 1.0.1
Typical Application Circuit
Features



Key Design Notes
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
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1. Schematic
LCD TV Power Supply
600V,15A
BD101,
Average efficiency of 25%, 50%, 75%, and 100% load conditions is higher than 95% at universal input.
Power factor at rated load is higher than 0.98 at universal input.
Total Harmonic Distortion (THD) at rated load is lower than 15% at universal input.
When auxiliary V
winding. The power consumption of R103 is quite high, so its power rating needs checking.
Because the input bias current of INV pin is almost zero, output voltage sensing resistors (R112~R115) should
be as high as possible. However, too-high resistance makes the node susceptible to noise. Resistor values need
to strike a balance between power consumption and noise immunity.
Quick-charge diode D106 can be eliminated. Without D106, system operation is normal due to the controller’s
highly reliable protection features.
Application
C114
,2.2n
R101,1M-
F
680nF
C102,
J
C115
,2.2n
F
220nF
C101,
ZNR101
,10D471
CC
supply is not available, V
Circuit for V
Circuit for V
FAN7930C
Device
CC
CC
. If external V
for another power stage thus components structure and values may vary.
Figure 45.
V
CC
for another power stage
CC
is used, this circuit is not needed.
CC
Input Voltage
power can be supplied through Zero Current Detect (ZCD)
90-265V
UF4004
Demonstration Circuit
10k,1W
C104,
D102,
Optional
12nF
600V 3A
R103,
Range
8
5
3
2
D106
V
ZC
D
Com
p
RD
Y
FAN7930C
CC
18
GND
6
Out
INV
AC
CS
230mH,
49:6
V
7
4
1
AUX
R108
LP101,EER3124N
4.7
R109
47
Rated Output
D103,1N414
Power
8
195W
20N60
FCPF
Q101
600V 8A
D105
Output Voltage
(Maximum
390V (0.5A)
Current)
DC OUTPUT
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