LG 32LD350 Troubleshooting Manual page 35

32LD350 P403 on Main to SMPS P201 Television Turn On Circuit
32LD350 P403 on Main to SMPS P201 Television Turn On Circuit
THREE STEP TURN ON PROCESS:
Stand-By: STBY_3.5V arrives on main. Powers up MStar (Micro /
Video Processor) Reset occurs. Then when a power on from the
Key board or IR arrives, 3 step process begins.
Step 1) RL_ON: Turns on the SMPS. 12V and 24V
12V arrives on Main, Power_Det sent to Mstar.
1b) MStar turns on IC405 and IC406.
Step 2) Panel_CTL: Turns on Panel VCC Q409, sent to panel.
Step 3) INV_CTL: Turns on the Backlights, to SMPS then Ballast.
SMPS
P201
PWR On
PWR_ON
1
24.19V
2
24.19V
24V
3
24.19V
4
5
6
7
8
9
10
3.5V_ST
11
12
13
14
15
16
11.97V
17
INV.On
18
11.97V
12V
19
0.59V
ERR Out
20
11.97V
21
4.49V
A.DIM 22
23
2.46V
PWM-DIM
24
11.97V
Panel VCC (LVDS 12V)
+5V Normal
MAIN Board
P403
+3.3V Normal
PWR ON
3.28V
1
2
24V
3
4
5
6
7
8
3.41V
9
3.41V
10
3.41V
11
3.41V
100uF
12
Gnd
13
Error_Out Pin 20: (Silk Screened A-DIM)
Gnd
14
Goes high (3.3V) when the backlights are told to
Gnd
come on. Goes back low when they light.
15
If it goes high again on the 5
Gnd
16
backlights, the set shuts off.
12V
17
3.32V
18
+3.3V Normal
19 12V
20
R473 0Ω
12V
21
22
A-DIM Pin 22: (Silk Screened P-DIM) Is not unsed.
N/C
23 N/C
24
R472 R479
0Ω 0Ω
11.97V
S
D
1.84V
Q409
G
4.99V L422
IC406
2
8
7
6
3.35V L421
IC405
8 2
7
6
3.28V
Q402
3
Q401
R406
0.89V
2 0V
4.7K
1
3.39V
L404
3.5V_ST
C401
attempt to fire the
th
R486 4.7KΩ
R424
0Ω
PWM-DIM
35
R439 10KΩ
12V
L412
R440 1.8KΩ
0.02V
11.97V
12V
100
L417
2.39V
R251
R459
10KΩ
Step 1b
11.97V
12V
L416
2.39V
R456
10KΩ
Step 1
R401
0.64V
R237
10K
100Ω
Pin 9
IR
P2401
R193
0Ω
Power
IC408
Det
+3.3V Normal
S5/S6
IC103
Reset
R419
Q405
R244
R421
1KΩ
100Ω
10KΩ
3.32V
0V
Step 3
R201
100Ω
R189
PWM2
100
November 2010
R429
Q406
Q407
47KΩ
0.68V 0.03V
F6
GPIO 138
Power On/Off 1
2
H5
GPIO137
R245
PANEL_CTL
100
Step 2
RL_On
E5
A4
SAR0 KEY 1
SAR1 B4
KEY 2
C4
IRIN Power On
Key 2
drops to
0.52V
IC100
H6
Mstar Pin 5
P2401
D4 HWRESET
3.4V
Normal
INV CTL
G5
GPIO 136
Error_Out
E9
GPIO 097
P-DIM
X100
AB12
PWM2
12MHz
XIN B3
XOUT A3
32LD350 3D-LCD