LG 49UF640 Series Service Manual page 17

4.2. V-COM Adjust (ONLY FOR EPI model)
4.2.1 Overview
▪ V-COM adj. Objective & How-it-works
- Objective: To r educe each Panel's V-COM voltage
deviation
- How-it-works: When V-COM gain in the adjust-OSD of
each SET is at default value, each SET can have flicker by
each Panel's V-COM voltage deviation. In order to prevent
flicker of each SET, find the desired each Panel's V-COM
voltage value.
- Adj. condition: normal temperature
1) Surrounding Temperature: 25 °C ± 5 °C
2) Warm-up time: About 5 Min
3) Surrounding Humidity: 20% ~ 80%
4.2.2 Equipment
(1) Color Analyzer: CA-310(LED Module : CH 14) or CM-H505
(2) Adj. Computer(During auto adj., RS-232C protocol is
needed)
(3) Adjust Remote control
(4) Signal : internal flicker Pattern in SET
▪ Color Analyzer Matrix should be calibrated using CS-100
4.2.3 Equipment connection MAP
Probe
USB to RS-232C
* If you want to use Signal Source,
you use TV internal Flicker pattern
4.2.4 Adj. Command (Protocol)
<Command Format>
CMD ID DATA CR RF
Flicker Analyzer
RS-232C
Computer
4.3. White Balance Adjustment
4.3.1. Overview
▪ V-com Adj. must begin as start command "va 00 00" , and
finish as end command "wb 00 ff"
▪ V-com adjust data
V-com Data
43 inch
hex
Max B4
Default 96
Min 78
V-com Data
49 inch
hex
Max 8B
Default 6D
Min 4F
V-com Data
55 inch
hex
Max 85
Default 68
Min 49
V-com Data
65 inch
hex
Max AB
Default 8D
Min 6F
▪ W/B adj. Objective & How-it-works
(1) Objective: To reduce each Panel's W/B deviation
(2) How-it-works : When R/G/B gain in the OSD is at 192, it
means the panel is at its Full Dynamic Range. In order to
prevent saturation of Full Dynamic range and data, one
of R/G/B is fixed at 192, and the other two is lowered to
dec
180
150
120
dec
139
109
79
dec
133
104
73
dec
171
141
111