LG 42LV5500 Training Presentation page 42

42LV5500 Power Supply Drawing
BD101
-
+
Q602
Q601
D603
RL101
F100
5A / 250V
SK100
W/Washer
AC In
Different Size
45V Line:
PWR-ON turns on the 45V
supply but it will only be 36V.
Note: A block of LEDs can not
be turned on with this voltage.
It will increase to 65V then drops
to 45V in less that 20 seconds
when the DRV-ON line goes
high.
P203
45V
L601
- -
+ +
C257 C256
D253
Q251
SMPS BOARD
p/n: EAY62169801
IC102
T101
Hot Ground Side
Q102
F101
Q101
3.15A / 250V
Stby: 399V
Run: 398.5V
Indicates Hot Ground
MODEL LGP4247-11SLPB
INPUT 100-240V~50/60Hz
3.5V = 1.8A
12V = 2.8A
OUTPUT
24V = 1.2A
59.2V = 1.6A
P202
VC_3B
VC_2C
Cold (Chassis)
Gnd side
VC_3A
VC_2D
P701
n/c
D251
P832
D252
D255
D256
Stand-By
3.5V
D261
P201
Source
D202
D201
T501
F501
IC502
1.6A / 250V
IC501
Stby: 397V
Run: 396.5V
SMPS TEST 1: To Force Power Supply On.
Disconnect P502 on Main board.
(A) Jump pins 9, 10, 11 or 12 (3.5V) to pin 1. Test Voltage Outputs 12V, 24V to Main and
36V to the Inverter Section of the SMPS. Remove AC power. Leave the jumper in place.
2.5A
SMPS TEST 2:
(B) Jump pins 9, 10, 11 or 12 (3.5V) to pin 18 (DRV-ON). Apply AC power, the
Backlights should turn on. Note, the LED B+ will now jump to 65V then back down to
45V.
Note; If there is a problem with a load from the panel backlights, you can remove AC and
Disconnect P202 or P203. When AC is reapplied, the Backlight LEDs should turn on for
about 4 seconds and then shut off.
42
P201 Connector "SMPS Board" To P502 "MAIN Board"
Pin Label STBY Run
ERROR
24 n/c n/c
23 n/c n/c n/c
22 PWM 0V 0.2V~3.3V
21 12V 0V 12V
20 n/c n/c n/c
19 12V 0V 12V
18 DRV-ON 0V 3.26V
17 12V 0V 12V
16 V_Sync (n/c) n/c n/c
13-15 Gnd Gnd Gnd
9-12 3.5V 3.55V 3.53V
5-8 Gnd Gnd Gnd
2-4 24V 0V 24.5V
1 PWR-ON 0V 3.41V
(1)
P-DIM1 (Digital Dimming) Global Pin 22 can vary
according to incoming video IRE level, OSD Backlight
setting and room light condition.
0.2V 0% to 3.3V 100% and the Intelligent Sensor.
Output from the Video Processor IC900.
May 2011 LCD-DV 42LV5500
Test1 Diode
0V 2.03V
0V OL
3.52V
OL
12V 0.48V
n/c OL
12V 0.48V
0V OL
12V 0.48V
n/c OL
Gnd Gnd
3.55V 2.63V
Gnd Gnd
24.41V 1.09V
3.55V 1.15V