FSDL0365 Fairchild Semiconductor, FSDL0365 Datasheet - Page 14

• Manufacturer Part Number: FSDL0365
• Description: Green Mode Fairchild Power Switch (FPSTM)
• Manufacturer: Fairchild Semiconductor

FSDL0165RN
Typical application circuit
1. Set Top Box Example Circuit (13W Output Power)
Multiple Output, 13W, 85-265VAC Input Power supply:
Figure 15 shows a multiple output supply typical for high
end set-top boxes containing high capacity hard disks for
recording. The supply delivers an output power of 13W
cont./15W peak (thermally limited) from an input voltage of
85 to 265 VAC. Efficiency at 9W, 85VAC is 75%.
The 3.3 V and 5 V outputs are regulated to ±5% without the
need for secondary linear regulators. DC stacking (the sec-
ondary winding reference for the other output voltages is
connected to the anode of D15. For more accuracy, connec-
tion to the cathode of D15 will be better.) is used to minimize
the voltage error for the higher voltage outputs. Due to the
high ambient operating temperature requirement typical of a
set-top box (60 C) the FSDL0165RN is used to reduce con-
duction losses without a heatsink. Resistor R5 sets the device
current limit to limit overload power.
Leakage inductance clamping is provided by R1 and C8,
keeping the DRAIN voltage below 650 V under all condi-
tions. Resistor R1 and capacitor C8 are selected such that R1
dissipates power to prevent rising of DRAIN Voltage caused
by leakage inductance. The frequency modulation feature of
FSDL0165RN allows the circuit shown to meet CISPR2AB
with simple EMI filtering (C1, LF1 and C2) and the output
grounded. The secondaries are rectified and smoothed by
D12, D13, D14,and D15. Diode D15 for the 3.4V output is a
Schottky diode to maximize efficiency. Diode D14 for the 5
V output is a PN type to center the 5 V output at 5 V. The 3.3
V and 5 V output voltage require two capacitors in parallel to
meet the ripple current requirement. Switching noise filter-
ing is provided by L3, L2 and L1. Resistor R15 prevents
14
~275VAC
85VAC
PERFORMANCE SUMMARY
Output Power:
Regulation
3.3V:
5.0V:
17.0V:
23.0:
Efficiency:
No load Consumption:
0.12W at 230Vac
2A/250V
FUSE
100pF
/400V
C1
40mH
LF1
100pF
/400V
C2
Figure15. 13W multiple power supply using FSDL0165RN
≥75%
±7%
±5%
±5%
±7%
13W
KBP06M
GreenFPS
400V
/47u
C7
47uF
50V
C6
D
S VccVfb
1
FSDL0165RN
33n
50V
D
C9
56K/1/
R3
4W
D
start
I_pk
5
6kR
R5
47K
R1
UF4004
D6
PC817
6.8n/
1kV
C8
UF4007
D5
30R
R4
Q1
FOD2741A
4
5
1
3
peak charging of the lightly loaded 23V output. The outputs
are regulated by the reference (TL431) voltage in secondary.
Both the 3.3 V and 5 V outputs are sensed via R13 and R14.
Resistor R22 provides bias for TL431and R21 sets the over-
all DC gain. Resistor R21, C209, R14 and R13 provide loop
compensation.
10
12
11
6
8
EGP20D
D12
EGP20D
PC817
TL431AZ
EGP20D
SB360
D13
330R
D14
D15
R21
20R
R15
R15
1000uF
monolithic
1000uF
C17
C15
C13
C11
1KR
/16V
R22
/16V
100uF
470uF
0.1uF/
/50V
/35V
L1
6.9K
C209
L3
L2
800R
R14
R12
1.5K
470uF
470uF
R13
/10V
C12
2.7K
/10V
C14
C16
220uF
100uF
/35V
/50V
R19
R20
0.005~0.20A
0.01~0.2A
+17.0V
+23.0V
+3.3V
0.4~0.8A
+5.0V
0.2~0.5A