V-Com Level Adjustment (Pk-65/66 Board); V-Com Adjustment (Pk-65/66 Board) - Sony MVC-CD250 Service Manual

7. V-COM Level Adjustment (PK-65/66 Board)

Set the common electrode drive signal level of LCD to the speci-
fied value.
Mode PLAY
Signal Arbitrary
Measurement Point Pin 8 of CN714 on SY-76 board
(PANEL_COM)
Measuring Instrument Oscilloscope
Adjustment Page A
Adjustment Address 87
Specified Value A = 6.14 ± 0.05 Vp-p
A = 5.42 ± 0.05 Vp-p
Adjusting method:
Order Page Address Data
1 0 01 01
2 A 02 03
3 4 F1 03
4 A 87
5 A 87
Processing after Completing Adjustments:
Order Page Address Data
1 A 02 00
2 4 F1 00
3 0 01 00
2H
Fig. 5-1-21
(MVC-CD400)
(MVC-CD250)
Procedure
Press PAUSE button.
Change the data and set the
voltage (A) to the specified
value.
Press PAUSE button.
Procedure
Press PAUSE button.
A

8. V-COM Adjustment (PK-65/66 Board)

Set the DC bias of the common electrode drive signal of LCD to
the specified value.
If deviated, the LCD display will be move, producing flicker and
conspicuous vertical lines.
Mode
Signal
Measurement Point
Measuring Instrument
Adjustment Page
Adjustment Address
Specified Value
Note: Perform "Contrast Adjustment" before this adjustment.
Adjusting method:
Order Page Address Data
1 0 01
2 A 02
3 4 F1
4 A 84
5 A 84
Processing after Completing Adjustments:
Order Page Address Data
1 A 02
2 4 F1
3 0 01
5-41
MVC-CD250/CD400
PLAY
Arbitrary
Check on LCD screen
A
84
The brightness difference between
the section-A and section-B is
minimum
Procedure
01
03 Press PAUSE button.
82
Change the data so that
brightness of the section A
and section B is equal.
Press PAUSE button.
Procedure
00 Press PAUSE button.
00
00
B A
A
B
B A
A B
Fig. 5-1-22