8-7
LCD Backlight Block Diagram
A7144BLLB
CURRENT
CONTR
OL
SWITCH
Q421
Q424
T401
CN401
LCD MODULE
INVER
TER CB
A
BA
CK
LIGHT
BA
CK
LIGHT
BA
CK
LIGHT
O
VER V
OL
TA
GE
PR
O
TECT
OR
Q422,423
1
2
1
2
CN402
CN403
1
2
9
8
3
5
2
6
1
4
10
7
CURRENT
CONTR
OL
SWITCH
Q441
Q444
T402
O
VER V
OL
TA
GE
PR
O
TECT
OR
Q442,443
9
8
3
5
2
6
1
4
10
7
CURRENT
CONTR
OL
SWITCH
Q461
Q464
T403
O
VER V
OL
TA
GE
PR
O
TECT
OR
Q462,463
9
8
3
5
2
6
1
4
10
7
O
VER V
OL
TA
GE
PR
O
TECT
OR
Q404
Q406
+10V REG.
O
VER CURERENT
PR
O
TECT
OR
Q425
Q405
SWITCHING
SWITCHING
SWITCHING
SWITCHING
INV+22V
TO
PO
WER
SUPPL
Y
BLOCK
DIA
GRAM
BA
CKLIGHT
-ADJ
Q401
SW+22V
T
O SYSTEM
CONTR
OL
BLOCK
DIA
GRAM
SWITCHING
Q407
NOTE: CBA AND PWB MEANS PRINTED WIRING BOARD.