Teclast X21, Service Manual

Page: 21 / 76

3.2.3 OLED module circuit
1. OLED module circuit schematic diagram is shown in the figure 3.2.3.1:
Figure 3.2.3.1 OLED circuit schematic diagram
2. Working principle: for 12V high voltage is required to lighten OLED, boosted circuit must be used
togther to fulfill it and the circuit includes two parts: boosted circuit and OLED jack circuit. In which,
boosted circuit is composed of boosted DC-DC LM2703 and peripheral circuit, VIN is power input, EN is
the enable end of LM2703, high level is effective, SW is high voltage output pin, FB is feedback pin, the
voltage value VOLED outputted by high voltage is achieved through selection the two divider resistance
and they satisfy the following relationship:
Seen from the above, VOLED is about, 12.2V. L25, C72 in circuit are energy storage inductor and
output capacitor of boosted circuit.
OLED jack circuit is connected with OLED jack of PNX0101 directly, the internal program of
PNX0101 controls the characters display of OLED, working state information of the player is displayed
through OLED to fulfill man-machine communication.
CN4
GND
C65
16V/104
R72
0R
R71
100K
L24
601
L25
CDRH3D16-4R7
R63
4.7K
VOLED
R74
0R*
R75
27K 1%
C68
22P
C71
475/X5R/6.3V
C63
103
C72
106/25V/1206
R64
4.7K
C67
104
R73
0R
P_VDD
VCC33
GND
L
C
D
_
3
V
3
EN1
_
R
E
S
E
T
L
C
D
_
R
D
2
L
C
D
_
D
B
1
2
L
C
D
_
D
B
4
2
L
C
D
_
D
/C
2
L
C
D
_
D
B
0
2
L
C
D
_
D
B
7
2
L
C
D
_
D
B
3
2
L
C
D
_
W
R
2
L
C
D
_
C
S
2
L
C
D
_
D
B
2
2
/R
E
S
E
T
L
C
D
_
D
B
6
2
L
C
D
_
D
B
5
2
V
O
L
E
D
R65
2M
L26
0R
R70
240K 1%
D8
MBR0520/SOD123
U10
TPS61040/LM2703
EN
4
VIN
5
FB
3
GND
2
SW
1
V
D
D
2
0
D
/C
#
1
5
D
5
7
N
C
1
V
C
O
M
H
3
D
3
9
W
R
#
1
4
IR
E
F
4
R
E
S
#
1
6
R
D
#
1
3
V
C
C
2
B
S
2
1
8
D
1
11
C
S
#
1
7
G
N
D
2
1
B
S
1
1
9
D
0
1
2
D
6
6
D
4
8
D
2
1
0
D
7
5
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