AN966 Datasheet, PDF (19/21 Pages) STMicroelectronics – The front-end stage of conventional off-line converters

AN966 APPLICATION NOTE
APPLICATION IDEAS
The L6561 is a versatile device. Besides the typical application as a PFC preregulator based on boost
topology, it fits also other applications and/or topologies. Some application hints are given in the follow-
ing.
Figure 17. Wide Range 50W PFC, Flyback Topology.
2A fuse
85 to 265
Vac
680 nF
1.5 MΩ
1.5 MΩ
3
220 pF
20 kΩ
4N35
1 µF
2
1
100 kΩ
2.4 kΩ
BYW80-150
220 kΩ
P6KE160P
220 kΩ
1N4937
22 µF
1N4148
8
39 kΩ
L6561
6
5
7
4
10 Ω
STP7NA60
2200 µF 2200 µF
25V
25V
4.7 nF
3.3 kΩ
4N35
TL431
24 Vdc / 2A
20 kΩ
22 kΩ
47 kΩ
1 nF
4.7 kΩ
0.33 Ω
1/2 W
Transformer spec:
Core: ETD29, 3C85 grade
Pri: 2 paralleled windings, 71 T/AWG27 each
Sec: 17 T, 5xAWG27 sandwiched
Aux: 10T, AWG32 evenly spaced
lgap: 1mm for 620 µH primary inductance
Figure 18. Power Factor Corrected Lamp Ballast using the L6569 driver.
FUSE
Bridge
176 to 265
Vac
NTC
100 C1
220nF
400V
R9 220K 1W
D1 BYT11600
R1
750K
C3 680nF
R3
68K 2
1
R1A ₅
750K
7
L6561
3
8
T1
STP5NA50
Q1
R4 10
R7
750K
R29
.6K
R7A
750K
D3 1N4148
DZ1 4.7V
C5
22µF
450V D2
1N4148
R2
8.2K
64
C2
10nF
C6
R11
10µF
22
R6
1
R8
9.53K
C8
P0102AA _10µF
SCR
R13 47
C12
820pF 600V
C11 100nF
DZ2
8
18V
1
STP6NB50
Q2
7 R15 10
R19
330K
R12
R17
2.2M
L6569 ^{6 10K}
STP6NB50
4
5
Q3
C9
100nF
2 16K
DZ3 5.6V ^R14
C10 R31
470nF 1.5M
R16 10
3
R18
10K
C13
470pF
C14
Q4 560pF
S170
R20
180K
C15
100nF
250V
L1
2.3mH
L2
2.3mH
C15A
100nF
250V
LP1
C16 R21 R23
6.8nF 820K 820K
630V
LP2
C17 ^{R22 R24}
6.8nF ^{1.5M 1.5M}
630V
R10 DZ4
56K 20V
D97IN682
R26
R30
C18
R25
2.2M
2.2M
1µF
82K
R28
D5 R27
1N4148 220
56K
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