Daewoo DVN-14F6N Service Manual page 42

2-3. SMPS BASIC OPERATING DESCRIPTION
1) Power supply block circuit
F801
AC 125V 4A
PWC1
Z801
SVC2710
VARISTOR
R804
2.2M(COMP)
1/2W
2) Initially starting operation
– When AC power supply is put in at first, the voltage which rectifies this.happens on the both Blocks of C806
This voltage flows through R806 and is the circuit which searchs the voltage of I801 V
starts or stops operating I801.
– Turning on the power supply, CTRL circuit starts operating by the funtion of START circuit, when it is charged to C807
through starting resistance R806 and V
– According to the multiplication(PRODUCT) of starting resistance R806 and C807, time is decided which CTRL citcuit
starts operating after putting AC input voltage. So, if the value of C807 is too high, It could be late for I801 to start.
– When CTRL circuit starts operating and the voltage of DRIVE wound wire (pin no #3) of T801 TRANS is up, I801
starts operating after rectification of D808 and C807.
– When the voltage of detect wound wire(pin no #4) T801 TRANS increases and is rectified through D807 and C809
and DC 32V is put in I801 sense(pin no #7), TRANS secondary voltage is established.
– When MAIN TR of power IC is off, energy which is charged to the primary is transtmitted through TRANS secondary
rectification DIODE.
D802-D805
:1S1888
C801
O.1U(M) D803 D805
L801
C803 C805
AC250V
TLF-472BE
D802 D804
C802 C804
Vin
1
1
START UP
PRE REA
7
SENSE
T.S.D
R1
terminal voltage goes to 8V (TYP.)
in
C802-C805
4700P 500V
R812
R803
120K
1 OHM 7W
1/2W
CEMENT
C806
330U(LWF)
200V
R806
36K
2W
R813
100K
1/4W
C809
C807
10U
220U
100V
25V
1801
STR-S5707
DR
4
R807
18 1W
S
PROPORTION
DVP LATCM
ORIVE
4
C808
220U
B
OCP
25V
3
DSC
D810
C
REF BYV950
1
E
2
C1 OCP
3
C3
C2 R2 C4
6
R832
R809
240(*200)
0.27(F)
1/4W
2W
39
T810
TSM-4242A3
8 9
7
10
123V
11
6
15V
5 12
D807
BYW95C
BYV95C
4 13
D808
BYV95C
15V
14
3
R819
2.2
1/4W
8.5V
2 15
R833
4.7K
1 16
1/4W
D809
BYV95C
L803
R815
MD-5
1.8K
1/4W
C823
3900P
630VPL
C824
4700P
R816 C822
AC400V
1K 1500P
1/4W 50V
TERMINAL (PIN No.#9) and
in
C827
1000P(HIKR)
2KV
C815
100U
160V
D814
BYW95C
C814
D813 C828
470U
0.01U
25V
D812 C812
BYV95C 470U
25V
C810
D811
470U
BYV95C
16V