Sony Cyber-Shot DSC-P72, Service Manual

Page: 53 / 74

6-33
DSC-P72
4. VG Center Adjustment (SY-85 board)
Set the VG signal center level of LCD panel to an appropriate level.
Note:
Do either of “Adjustment without Using Digital Voltmeter” or
“Adjustment Using Digital Voltmeter”.
4-1. Adjustment without Using Digital Voltmeter
Mode PLAY ( )
Signal Arbitrary
Measurement Point Data of page: 40, address: 11, 12
Measuring Instrument
Adjustment Page 4F
Adjustment Address 8B
Specified Value 205 to 20D
Adjusting method:
Order Page Address Data Procedure
1 00 01 01 Set the data.
2 40 F1 01 Write the data.
3 4F 02 03 Write the data.
4 40 10 00 Write the data.
5 40 10 90 Write the data.
6 40 11 Read the data, and this data is
named D
11A
.
7 40 12 Read the data, and this data is
named D
12A
.
8 40 10 91 Write the data.
9 40 11 Read the data, and this data is
named D
11B
.
10 40 12 Read the data, and this data is
named D
12B
.
11 Calculate DA and DB using
following equation.
(Hexadecimal calculation.)
(Note1)
DA = (D
11A
×
4+ D
12A
/ 40)
DB = (D
11B
×
4+ D
12B
/ 40)
12 Calculate the signal level using
following equation.
(Hexadecimal calculation.)
Signal level = (D
A
+ D
B
) / 2
13 When the signal level satisfies
the specified value proceed to
step 16, in case of others
proceed to step 14.
14 4F 8B Change the data. (Note2)
(The data should be “00” to
“7F”.)
15 4F 8B Write the data, and return to step
4.
16 4F 02 00 write the data.
17 40 F1 00 Write the data.
18 00 01 00 Set the data.
Note1: When dividing D
12A
or D
12B
by 40. If there is a fraction below
decimal point, truncate it.
Note2:
When the signal level is smaller than specified value, increase the
data.
4-2. Adjustment Using Digital Voltmeter
Mode PLAY ( )
Signal Arbitrary
Measurement Point CL803 (Pin
ws
of IC801) (VG)
Measuring Instrument Digital voltmeter
Adjustment Page 4F
Adjustment Address 8B
Specified Value A = 7.00 ± 0.05V
Adjusting method:
Order Page Address Data Procedure
1 00 01 01 Set the data.
2 40 F1 01 Write the data.
3 4F 02 03 Write the data.
4 4F 8B Change the data and set the DC
voltage (A) to the specified value.
(The data should be “00” to “7F”.)
5 4F 8B Write the data.
6 4F 02 00 Write the data.
7 40 F1 00 Write the data.
8 00 01 00 Set the data.