LG 47LD455B, Service Manual

Page: 12 / 42

4.5. V-COM Adjust
(Only M+S models which use LGD module)
- Why need Vcom adjustment?
A
The Vcom (Common Voltage) is a Reference Voltage of
Liquid Crystal Driving.
-> Liquid Crystal need for Polarity Change with every frame.
- Adjust sequence (Method 1)
· Push ‘PIP’ key.
· If there is no flicker at default value, turn down or turn up
until no flicker, push ‘OK’ key to store.
· Push ‘Exit’ key to exit.
- Adjust sequence (Method 2)
· Enter ‘EZ ADJUST’ mode by pushing “ADJ” key.
· Select and enter ‘12. V-Com’ mode.
· If there is no flicker at default value, turn down or turn up
until no flicker, push ‘OK’ key to store.
· Push ‘Exit’ key to exit.
4.6. Outgoing condition Configuration
- Push ‘IN-STOP’ key, the in-stop processing will start.
If processing i complete, TV will turn off automatically.
(Must not AC power OFF during blinking)
4.7. Internal pressure
Confirm whether is normal or not when between power
board's ac block and GND is impacted on 1.5kV(dc) or
2.2kV(dc) for one second.
- 12 - LGE Internal Use Only Copyright © 2011 LG Electronics. Inc. All right reserved.
Only for training and service purposes
V-Com
V-Com
425
EZ ADJUST
0. Tool Option1
1. Tool Option2
2. Tool Option3
3. Tool Option4
4. Tool Option5
5. Country Group
6. ADC Calibration
7. White Balance
8. 10 Point WB
9. Test Pattern
10. EDID D/L
11. Sub B/C
12. V-Com
13. P-Gamma
Press ( ) to save.
Row Li ne
Column Line
C
LC
C
ST
Pane l
S
Y
S
T
E
M
Gat
e
Driv
e
IC
So urce D r i v e I C
Circuit Block
Ti m i n g
Co nt r o ll e r
Po w e r
Blo ck
V
COM
Ga mma
Re f e r e nce V o ltage
Gamm a R eference
Volta ge
Da ta (R ,G,B ) & C ont ro l s ignal
Con t rol si gnal
Data (R ,G,B ) &
Con t rol si gnal
In
te
r
fa
c
e
TFT
Po w e r I n p u t Power Input
Da t a I n p u t Da t a I n p u t
V
COM
Liquid
Crys tal
V
COM