LG 42LH90 Manual page 93

INVERTER CN3-CN4 INFO.
CN3
IC303
27.5V Line on CN3
3 21
2
Y301 (12Mhz)
Pins 1-2 (Out_M2) Pins 1-2 (Out_M3)
1 3 2 2
1.76Vp/p 1.25Vp/p
Pins 13-14 (Out_M2) Pins 13-14 (Out_M3)
IC302
IC301 Pins 16-17 (Out_M2) Pins 16-17 (Out_M3)
D302 Processor
Pins 26-29 (Out_M2) Pins 26-29 (Out_M3)
CN305
D302 blinks
Q19 Pins 31-32 (Out_M4) Pins 31-32 (Out_M1)
Q50
1Hz OK n/c
Pins 43-44 (Out_M4) Pins 43-44 (Out_M1)
Q20
Q49
IC5
Pins 46-47 (Out_M4) Pins 46-47 (Out_M1)
Q21
Q48
Pins 58-59 (Out_M4) Pins 58-59 (Out_M1)
IC14
CN306
Q22
Q47
ZD304
ZD303
(Pin 6)
Q23
Q46
3.46Vp/p
Q24
IC13
Q45
IC6 n/c
(Pin 4)
Q44 Q25
3.48Vp/p
CN307
Q43
Q26
(Pin 1)
3.54Vp/p
Q42 Q27
IC10 IC7
Q41 Q28
Q40 Q29
P1200 "MAIN" to P101 "Front IR / LED
Q39
Q30
Pin Label Label STBY STBY
Q38
Q31
1 SCL 0.57V
IC9 IC8
Q37
Q32
2 SDA 0.57V
Q36
Q33
3 Gnd Gnd
Q35
Q34
4 Key1 3.2V
INVERTER Board
5 Key2 3.2V
IC4 IC15
1 1
6 5V ST 5.1V
2 2
2 2
3 3 CN4
7 Gnd Gnd
CN3
8 Warm ST 0V
IC1 IC3
9 IR 3.5V
M1-M4
10 Gnd Gnd
(27.5V)
L5
CN1
11 3.3V_ST 3.2V
C40
+
12 POWER On/Off 0V
-
5 4 3 2 1
680uF
ZD3
F2
35V
2A/125V
24V
CN1 "INVERTER" TO P203 "SMPS"
F1
Pin Label STBY
Q5 Q4
12A/65V
L1
24V
M4 D3
14 AGP 0V
C12
+
680uF
+ -
1
13 Ext_VBR_B 0V
35V D2
-
L2
12 ON/OFF 0V
11 NC 0.47V
Q12 Q11 D7
C3
L3
M3
10 GND GND
C27
+
680uF
35V D8
9 GND GND
-
L4
8 GND GND
+ -
Q205 Q204 D203 7 GND GND
L201
M2
C212
+ 6 GND GND
680uF
35V D202 C203
1-5
- VIN 0V
L202
1
Ext_VBR_B same as (P-DIM)
D207
Q212 Q211
M1
L203
C227
+
IC201
680uF
35V
Front PWB
-
D208
L204
P100 Assembly
P102
Q19 through Q50
IR Receiver
Note: Each output driver (switch) has a TP to the left and right
representing a "V" which indicates a Block of LEDs.
Intelligent Sensor
V34 represents Pin 23 of CN4
V33 represents Pin 24 of CN4
Grounding these points when the 27.6V supplies are working will
cause the entire Block of Backlight LEDs to turn on.
(100mA to light one block)
42LH90 INTERCONNECT DIAGRAM
P203 "SMPS" TO
CN1 "INVERTER"
CN4
Diode
27.5V Line on CN4
Pin Label
Check
14 AGP OPEN
13 Ext_VBR_B OPEN
12
ON/OFF OPEN
11 NC OPEN
10
GND GND
9 GND GND
8 GND GND
7 GND GND
6 GND GND
1-5
VIN 0.74V
For Voltages see CN1 Table
Run Diode Check
P203
Switch Mode Power Supply
3.3V Open
D215
Open
3.3V
Gnd Gnd
Open D213
3.2V
3.2V Open
Open
5.1V
Gnd Gnd
0V Open
D211
3.5V Open
Gnd Gnd
3.2V Open
3.2V Open
159.9V in Stand-By
F101
190 in Run
3.15A
Diode
Run
250V
Check Hot
Gnd
0V OPEN
D601
0.33V-3.2V OPEN
4.65V 1.6V
1.66V OPEN
Q602
GND GND
GND GND
L601
Q601
GND GND
GND GND
GND GND
24.0V 2.9V
P102 "Front IR / LED PWB to P100 Keys
P101
Diode
Pin Label STBY Run
Check
1 Key1 3.2V 3.2V Open
2 Gnd Gnd Gnd Gnd
3 Key2 3.2V 3.2V Open
P100
4 Gnd Gnd Gnd Gnd
LED Board
J1
Pin 59 -4.9V Pin 3,4,5 16V
TO TFT MODULE
3.3V
Pin 57 26V Pin 7,8
TO TFT MODULE
T-CON
P/N EAT60665101
CN5
(TFT Driver)
VCC
3.3V
U12
1) 0V UC1
1
Gnd Protect
2) 1.19V 2 2
3
3) 3.3V
U11 C
FL1
3.3V
Q1
1) Gnd U10 8) 3.34V
7) 3.09V B
2) Gnd
E
3) Gnd 6) 3.34V 2.78V
3.3V
F1 (12V)
4) Gnd 5) 3.34V 125V /
3A
CN1 CN2
12V LVDS Pins 48~51
SMPS TEST 1: To Force
Power Supply On.
SMPS
Disconnect P700 on Main
PWB.
Jump pin 7,8,9 or 10 (5V) to
P201
T101
pin 2 using a 100Ω resistor.
(Test Voltage Outputs 12V,
and 24V).
SMPS TEST 2: Jump pin 2 to
pin 20 (INV-ON).
(Backlights and all voltages
IC102
should turn on).
D201
IC503
IC502
T501
IC501
Q101
Q102
Hot
Gnd
F100 SK100
5A
250V
SK101
Tuner
Main Power SW
P201 "SMPS" to P700 "Main"
Pin
16V Pin 2 -4.9V
Pin Label STBY
56,57,58
3.3V
Pin 4 26V
Pin 53,54
2 PDIM
TO TFT MODULE
24
23 nc
CN4
22 Err Out
FL2
Gnd Protect
21 1 A.DIM
L2
-4.9V
Gnd
D9
20 INV.ON
27V
3.3V
19 nc
-2.4V
D10
20.
14.25
D7
5V 17,18 24V
V
15,16 Gnd
U5 B+ ( 12V )
U5 U5
13,14
12V
26V
16V
L1
11,12
R702 R701 Gnd
16V
7,8,9,10 5V 5.15V
VDD
( 12V ) D8
3,4,5,6 Gnd
16V
2 PWR-On
1 nc
1
ADIM Pin 21
12V LVDS Pins 1~4 Fixed and not
used
P3500
12V LVDS
Pins 1~4
IC3504 IC3502
Operates at
IC3503
P3501
high
temperature
IC3500
Q705
Q704
X3500
Q703
25Mhz
Q706 B
IC704
C
E L726
P700
B
C
E
B
E B
C
E
1 2
IC2
C
IC705
IC107
L710
Q702 3
L718
IC706
Q701
IC701
IC105
E B
C
IC1
P1200
SW100 IC104
IC702
IC100
Micro/Video
E
C B Q106 Processor
E
Q105
Mstar
B
L607 C X100
P600
2
IC103
3
12Mhz
1
IC600
Q600
B A1
C
C
E A2
D102
IC1002
L606
IC703
IC1003
Speakers
P700 "Main" to P201 "SMPS"
Diode
Diode Check
Run
Check
1 Open
Open
0V 3.2V
2.6V
2
nc nc nc
3,4,5,6 Gnd
0V 0V Open
7,8,9,10 1.1V
0V 1.66V Open
11,12 Gnd
0V 4.65V Open
13,14 2.2V
nc
nc nc
15,16 Gnd
0.74V
0V 24V
17,18 Open
Gnd Gnd Gnd
19 Open
0.98V
0V 12V
20 2.9V
Gnd
Gnd Gnd
21 Open
5.15V Open
Open
22
Gnd
Gnd Gnd
23 Open
1.6V
0V 4.98V
24 1.3V
nc nc nc
For Voltages see P201
2
PDIM Pin 24 can vary according to type of signal
being processed and the OSD Backlight setting.
0.6V 0% to 3.3V 100%.
Output from the IC100 Video Processor.
P3502
42LH90
MAIN BOARD
IC3502
Tru- SW3500
Not Used
Motion/
Dimming
IC3505
Grayed Out Components
are on the Back
For Main board component
Voltages see PG 3 of
Interconnect Diagram
IC800 IC901
X800
12Mhz
IC801
P101
N/A
IC900
IC707
IC708
IC101
E
C
L712
B
Q100
IC1000
IC1001
IC102 IC1202
D1000
D1000
X1005
25Mhz
D500
A1 A2
Q1000
E C
C
E C IC1004
IC1201 B
IC502 B
IC501
Q1001
IC1203 Analog Video
IC1200
(19)
C A1
SIF (16)
D1223
A2
Dig DIF- (13)
Dig DIF+ (12)
TU1001 Tuner
TDVW-H103F
Clock (9)
Data (8)
Q1200
Tuner 5V_TU
B
C (4)
E
(1)