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42/50G2 PDP modules vertical line
issue repair method

Contents

I. Tv models using G2 panels.
II. Vertical noise type.
A1. Vertical noise failure cause.
A3. Measuring diode value.




2009. 7. 09
HE Company / LGERS / Design Gr.
A. Manager Jose Luis Ortiz Q.
. TV models using G2 PDP panels.
There are reported two kind of vertical noise in the field related to PDP panels 42G2 and 50G2 series caused by control board assembly.
1.- Vertical line with same interval.
2.- Vertical line without same interval.
This bulletin shows analysis and repair method for both kind of issues.

TV MODELS USING 42G2 SERIES PANELS. TV MODELS USING 50G2 SERIES PANELS.
No Model Name No Model Name No Model Name No Model Name
1 42PQ20-UA.ACCLLHR 27 42PQ20-UA.ACCALHR 1 50PQ20-UA.ACCLLHR 27 50PQ20-UA.ACCALHR
2 42PQ20-UA.ACCLLJR 28 42PQ20-UA.AUSALHR 2 50PQ20-UA.ACCLLJR 28 50PQ20-UA.AUSALHR
3 42PQ20-UA.AUSLLHR 29 42PQ20-UA.AWMALHR 3 50PQ20-UA.AUSLLHR 29 50PQ20-UA.AWMALHR
4 42PQ20-UA.AUSLLJR 30 42PQ30-UA.ACCALHR 4 50PQ20-UA.AUSLLJR 30 50PQ30-UA.ACCALHR
5 42PQ20-UA.AWMLLHR 31 42PQ30-UA.AUSALHR 5 50PQ20-UA.AWMLLHR 31 50PQ30-UA.AUSALHR
6 42PQ20-UA.AWMLLJR 32 42PQ30-UD.AWMALHR 6 50PQ20-UA.AWMLLJR 32 50PQ30-UD.AWMALHR
7 42PQ30-UA.ACCLLHR 33 42PQ30C-UA.AUSALHR 7 50PQ30-UA.ACCLLHR 33 50PQ30C-UA.AUSALHR
8 42PQ30-UA.ACCLLJR 34 42PQ30R-MA.AWCALJR 8 50PQ30-UA.ACCLLJR 34 50PQ30R-MA.AWCALJR
9 42PQ30-UA.AUSLLHR 35 42PQ30R-MA.AWFALJR 9 50PQ30-UA.AUSLLHR 35 50PQ30R-MA.AWFALJR
10 42PQ30-UA.AUSLLJR 36 42PQ30R-MA.AWHALJR 10 50PQ30-UA.AUSLLJR 36 50PQ30R-MA.AWHALJR
11 42PQ30-UD.AWMLLHR 37 42PQ30R-MA.AWPALJR 11 50PQ30-UD.AWMLLHR 37 50PQ30R-MA.AWPALJR
12 42PQ30-UD.AWMLLJR 38 42PQ60-UA.ACCALHR 12 50PQ30-UD.AWMLLJR 38 50PQ60-UA.ACCALHR
13 42PQ30C-UA.AUSLLHR 39 42PQ60-UA.AWMALHR 13 50PQ30C-UA.AUSLLHR 39 50PQ60-UA.AWMALHR
14 42PQ30R-MA.AWCLLJR 40 42PQ60R-MA.AWCALJR 14 50PQ30R-MA.AWCLLJR 40 50PQ60R-MA.AWCALJR
15 42PQ30R-MA.AWFLLJR 41 42PQ60R-MA.AWFALJR 15 50PQ30R-MA.AWFLLJR 41 50PQ60R-MA.AWFALJR
16 42PQ30R-MA.AWHLLJR 42 42PQ60R-MA.AWHALJR 16 50PQ30R-MA.AWHLLJR 42 50PQ60R-MA.AWHALJR
17 42PQ30R-MA.AWPLLJR 43 42PQ60R-MA.AWPALJR 17 50PQ30R-MA.AWPLLJR 43 50PQ60R-MA.AWPALJR
18 42PQ31-UD.AWMLLHR 18 50PQ31-UD.AWMLLHR
19 42PQ60-UA.ACCLLHR 19 50PQ60-UA.ACCLLHR
20 42PQ60-UA.ACCLLJR 20 50PQ60-UA.ACCLLJR
21 42PQ60-UA.AWMLLHR 21 50PQ60-UA.AWMLLHR
22 42PQ60-UA.AWMLLJR 22 50PQ60-UA.AWMLLJR
23 42PQ60R-MA.AWCLLJR 23 50PQ60R-MA.AWCLLJR
24 42PQ60R-MA.AWFLLJR 24 50PQ60R-MA.AWFLLJR
25 42PQ60R-MA.AWHLLJR 25 50PQ60R-MA.AWHLLJR
26 42PQ60R-MA.AWPLLJR 26 50PQ60R-MA.AWPLLJR




The People Company 1/6
I. PDP module (G2 models) Vertical Noise type

There are two types of Picture (Vertical) noise upon DDR Memory for 42/50G2 PDP module.



1. Vertical line with same interval (16pixels) 2. Vertical line without same interval (8pixels, 16pixels or
32pixels)




8pixel




shift


The People Company 2/6
I. PDP module (G2 models) Vertical Noise type

1. Vertical line with same interval
(16pixels)


CHECK PROCEDURE:
This problem is mostly related to failure in DQ signal paths
from DDR2 memory IC251 to BGA IC201.

A. Check the components solder quality, foils and via holes
integrity. A
B. Press BGA IC firmly to check for bad solder.
B
Refer to A1 figure in page 5.




Check points



C. Check diode value of the16 DQ lines using multi-meter,
GND(+)-to-DQ line(-) (refer to A3 picture in the last slide).
Normal diode voltage drop is (0.4 to 0.5 Vdc).


If everything is OK and failure persist, change the control board assy.


The People Company 3/6
I. PDP module (G2 models) Vertical Noise type

2. Vertical line without same interval (8pixels, 16pixels or
32pixels).
8pixel




CHECK PROCEDURE:
A. Check the control board DQS Resistors coming out from DDR
memory to BGA IC (backside R282 , R283 , R284 , R285)

- DQS (local clock function) resistor value must be 470.

If 1K resistor value is found, change to 470 (1 470).

- 1 has some potential probability to cause vertical lane when
repeatedly connected and disconnect of LVDS cable.

B. Check diode value of the 4 DQS lines.
(refer to A3 picture in the last slide).
Normal diode voltage drop is (0.4 to 0.5 Vdc).


If everything is OK and failure persist, change the control board assy.


The People Company 4/6
A1. Vertical Noise Failure cause
Possible Failure Cause of Picture (Vertical) Noise upon DDR Memory






ASIC Memory


PCB






Failure cause:
Pin fail : Diode check with multi-meter.
Resistor Crack and soldering problem : visual inspection
Via hole crack : Diode check, resistor check visually and using multi-meter.
Ball crack and soldering problem in BGA IC's: Press devices toward PCB




The People Company 5/6
A3. Measuring Diode value of DQ and DQS

Diode check using Multi-meter


-
Address, Command

DQ

Clk


DQS
Memory



ASIC

+




GND
The People Company 6/6