TOP243 View Datasheet(PDF) - Power Integrations, Inc
Part Name
Description
Manufacturer
TOP243 Datasheet PDF : 52 Pages
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TOP242-250
Multiple Output, 60 W, 185-265 VAC Input Power Supply to the relatively large size of C2). An optional MOV (RV1)
Figure 44 shows a multiple output supply typical for high end extends the differential surge protection to 6 kV from 4 kV.
set-top boxes or cable decoders containing high capacity hard
disks for recording. The supply delivers an output power of Leakage inductance clamping is provided by VR1, R5 and C5,
45 W cont./60 W peak (thermally limited) from an input keeping the DRAIN voltage below 700 V under all conditions.
voltage of 185 to 265 VAC. Efficiency at 45 W, 185 VAC is Resistor R5 and capacitor C5 are selected such that VR1
≥ 75%.
dissipates very little power except during overload conditions.
The frequency jittering feature of TOPSwitch-GX allows the
The 3.3 V and 5 V outputs are regulated to ±5% without the circuit shown to meet CISPR22B with simple EMI filtering
need for secondary linear regulators. DC stacking (the (C1, L1 and C6) and the output grounded.
secondary winding reference for the other output voltages is
connected to the cathode of D10 rather than the anode) is used The secondaries are rectified and smoothed by D7 to D11, C7,
to minimize the voltage error for the higher voltage outputs.
C9, C11, C13, C14, C16 and C17. Diode D11 for the 3.3 V
output is a Schottky diode to maximize efficiency. Diode D10
Due to the high ambient operating temperature requirement for the 5 V output is a PN type to center the 5 V output at 5 V.
typical of a set-top box (60 °C) the TOP246Y is used to The 3.3 V and 5 V output require two capacitors in parallel to
General Information & Table of Contents reduce conduction losses and minimize heat sink size. Resis- meet the ripple current requirement. Switching noise filtering
tor R2 sets the device current limit to 80% of typical to limit is provided by L2 to L5 and C8, C10, C12, C15 and C18.
overload power. The line sense resistor (R1) protects the
TOPSwitch-GX from line surges and transients by sensing when
Resistor R6 prevents peak charging of the lightly loaded 30 V
output. ThePourtpoutds aure rcegtulaStedeulsiengcatseocorndGaryurefiedrenece 1
the DC rail voltage rises to above 450 V. In this condition the (U3). Both the 3.3 V and 5 V outputs are sensed via R11 and
TOPSwitch-GX stops switching, extending the input voltage
withstand to 496 VAC which is ideal for countries with poor
R10. Resistor R8 provides bias for U3 and R7 sets the overall
Data Sheets 2 DC gain. Resistor R9, C19, R3 and C4 provide loop compen-
power quality. A thermistor (RT1) is used to prevent sation. A soft-finish capacitor (C20) eliminates output
premature failure of the fuse by limiting the inrush current (due overshoot.
Application Notes 3
PERFORMANCE SUMMARY
Output Power:
45 W Cont./60 W Peak
Regulation:
3.3 V:
5 V:
12 V:
± 5%
± 5%
± 7%
18 V:
30 V:
Efficiency:
± 7%
± 8%
≥75%
No Load Consumption:
0.6 W
VR1
R5
P6KE170 68 kΩ
2W
C6
2.2 nF
Y1
D1-D4
1N4007 V
C5
1 nF
400 V
D6
1N4937
Design Ideas
R6 D7
10 Ω UF4003
D8
UF5402
C7
47 µF
50 V
30 V @
L2
3.3 µH
Design Tools C8
10 µF
0.03 A
3A
50 V
18 V @
0.5 A
D9
UF5402
C9
330 µF
25 V
L3
C10
Quality and Reliability 3.3µH
3A
100 µF
25 V
12 V @
0.6 A
D10
BYV32-200
C11 C13 C16
390 µF 1000 µF 1000 µF
35 V 25 V 25 V
L4
3.3 µH
5A
C12
100 µF
25 V
5V@
C14 PaL5ckCa15 ge Informat3.i2oA n
1000 µF
3.3 µH 220 µF
25 V
5A 165 V
3.3 V @
3A
D11
MBR1045
DPA-Switch C17
1000 µF
DC-DC C18
220 µF
16 V
Seminar
25 V
RTN
L1
20 mH
0.8A
C1
0.1 µF
X1
RV1
275 V
14 mm
F1
J1
3.15 A
RT1
L
10 Ω
1.7 A
N
C2
68 µF
LinkSwitch & TinySwitch-II AC-DC Seminar
400 V
R1
2 MΩ
1/2 W
T1
D6
1N4148
C3
1 µF
50 V
R7
150 Ω
R10
15.0
kΩ
TOPSwitch-GX U2
LTV817
R8
1 kΩ
ARC11 -DC
Seminar
9.53
D L TOPSwitch-GX
kΩ
CONTROL
R9 C19
Sales Representatives and Distributors TOP246Y
U1 S
C
XF
C3
0.1 µF
50 V
R3
6.8 Ω
3.3 kΩ 0.1 µF
.R2
9.08 kΩ
C5
47 µF
10 V
C20
22 µF
10 V
U3
TL431
R12
10 k
PI-2693-033001
4
5
6
7
8
9
10
11
Figure 44. 60 W Multiple Output Power Supply using TOP246.
24 H
9/02
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