LG 26LV2500, Service Manual

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LGE Internal Use Only Copyright © 2011 LG Electronics. Inc. All rights reserved.
Only for training and service purposes
4. White Balance Adjustment
4.1 Overview
▪ W/B adj. Objective & How-it-works
- Objective: To reduce each Panel’s W/B deviation
- How-it-works: When R/G/B gain in the OSD is at
192, it means the panel is at its Full Dynamic R-
ange. 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 find the desired value.
-Adj. condition : normal temperature
1) Surrounding Temperature: 25±5
2) Warm-up time: About 5 Min
3) Surrounding Humidity: 20% ~ 80%
4. 2 Equipment
1) Color Analyzer: CA-210 (LED Module : CH 14)
2) Adj. Computer(During auto adj., RS-232C protocol is
needed)
3) Adjust Remocon 4) Video Signal Generator MSPG-
925F 720p/216-Gray(Model:217, Pattern:78)
→ O nly when internal pattern is not available
▪ Color Analyzer Matrix should be calibrated using CS
-1000
4.3 Equipment connection MAP
Color Analyzer
Computer
Pattern Generator
※
※ If TV internal pattern is used, not
Signal Source
Probe
RS-
232C
RS-
232C
RS-
232C
RS-232C COMMAND
[CMD ID DATA] Explanation
wb 00 00 Begin White Balance adj.
wb 00 10 Gain adj.(internal white pattern)
wb 00 1f Gain adj. completed
wb 00 20 Offset adj.(internal white pattern)
wb 00 2f Offset adj. completed
wb 00 ff End White Balance adj.
(internal pattern disappears )
Ex) wb 00 00 -> Begin white balance auto-adj.
wb 00 10 -> Gain adj.
ja 00 ff -> Adj. data
jb 00 c0
...
...
4.4 Adj. Command (Protocol)
<Command Format>
START 6E A 50 A LEN A 03 A CMD
A 00 A VAL A CS A STOP
- LEN: Number of Data Byte to be sent
- CMD: Command
- VAL: FOS Data value
- CS: Checksum of sent data
- A: Acknowledge
Ex) [Send: JA_00_DD] / [Ack: A_00_okDDX]
▪
RS-232C Command used during auto-adj.
wb 00 1f -> Gain adj. complete
*(wb 00 20(start), wb 00 2f(endc)) -> Off-set adj.
wb 00 ff ->End white balance auto adj.
▪ Adj. Map
Adj. item Command
(lower caseASCII) Data Range
(Hex.) Default
(Decimal) Details
CMD1 CMD2 MIN MAX
R Gain j g 00 C0 TBD
G Gain j h 00 C0 TBD
B Gain j i 00 C0 TBD
R Cut TBD
G Cut TBD
Cool
B Cut TBD
R Gain j a 00 C0 TBD
G Gain j b 00 C0 TBD
B Gain j c 00 C0 TBD
R Cut TBD
G Cut TBD
Medium
B Cut TBD
R Gain j d 00 C0 TBD
G Gain j e 00 C0 TBD
B Gain j f 00 C0 TBD
R Cut TBD
Warm
G Cut TBD
4.5 Adj. method
4.5.1 Auto adj. method
1) Set TV in adj. mode using POWER ON key
2) Zero calibrate probe then place it on the center of the
Display.
3) Connect Cable(RS-232C).
4) Select mode in adj. Program and begin adj.
5) When adj. is complete (OK Sing), check adj. status pre
mode (Warm, Medium, Cool) 6) Remove probe and RS-
232C cable to complete adj.
▪ W/B Adj. must begin as start command “wb 00 00” , and
finish as end command “wb 00 ff”, and Adj. offset if need .