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Feed-back Circuit
F3
F1
TP801
TP803
TP804
TP802
OZ9933
IC801
VSEN
1
SST/CMP
2
CT
3
RT1
4
GNDA
5
PDR2
6
GNDP
7
NDR2
8
NDR1
9
PDR1
10
VDDA
11
TIMER
12
PWM
13
ISEN
14
OVPT
15
ENA
16
D801
BAV99
A
J
K
R831
511 F
C831
0.22U K
R834
1M
.
.
.
.
T 801
6
3
5
4
8
2
7
1
R819
100K
R820
20K F
C820
470P J
C819
5PF D
C821-2
R822
20K F
R821
100K
C822
470P J
C821
5PF D
C815
100P J
C816
100P J
CN801
2K62272102
1
1
2
2
CN802
2K62272102
1
1
2
2
D809
LL4148
A
K
R816
2.2K
R815
2.2K
R827
365 F
C814
0.033U K
D805
BAV99
A
J
K
Fig. 2
Fig. 2 shows the feedback circuit consists of a lamp, R816, D805, R827 and C814.
With the lamp current through D805, a half sine-waveform voltage signal is produced.
We may get the Maximum value through R827/C814.
After OZ9933 gets the feedback voltage signal from PIN14, the duty of the full-bridge
driver outputs is decided.
Summary of Contents for G2420HD
Page 10: ...10 3 1 2 6 Support Timings...
Page 51: ...51 5 4 Packing...
Page 56: ...56 5 6 4 2 AC DC converter...