LG PDP42V5 Series User manual

PDP MODULE
SERVICE MANUAL
CAUTION
1. BEFORE SERVICING THE PDP MODULE,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
2. WHEN REPLACEMENT PARTS ARE REQUIRED, BE SURE TO USE
REPLACEMENT PARTS SPECIFIED BY THE MANUFACTURER..
MODEL : PDP42V5####
Korean English

- 2 -
PDP Module is a display device to be divided into a Panel part
and a Drive part. The Panel part consists of
Electrodes, Phosphor, various dielectrics and gas, and the Drive
part includes electronic circuitry and PCB.
When using/handling this PDP Module, pay attention to the
below warning and cautions.
Warning?
Indicates a hazard that may lead to death or injury if the
warning is ignored and the product is handled incorrectly.
Caution?
Indicates a hazard that can lead to injury or damage to
property if the caution is ignored and the product is handled
incorrectly.
¥.WARNING
(1) Do not supply a voltage higher than that specified to this
product. This may damage the product and may cause a
fire.
(2) Do not use this product in locations where the humidity is
extremely high, where it may be splashed with water, or
where flammable materials surround it.
Do not install or use the product in a location that does no
satisfy the specified environmental conditions. This may
damage the product and may cause a fire.
(3) If a foreign substance (such as water, metal, or liquid) gets
inside the product, immediately turn off the power.
Continuing to use the product, it is may cause fire or
electric shock.
(4) If the product emits smoke, and abnormal smell, or makes
an abnormal sound, immediately turn off the power.
Continuing to use the product, it may cause fire or electric
shock.
(5) Do not disconnect or connect the connector while power to
the product is on. It takes some time for the voltage to drop
to a sufficiently low level after the power has been turned
off.
Confirm that the voltage has dropped to a safe level before
disconnecting or connecting the connector.
(6) Do not pull out or insert the power cable from/to an outlet
with wet hands. It may cause electric shock.
(7) Do not damage or modify the power cable. It may cause
fire or electric shock.
(8) If the power cable is damaged, or if the connector is loose,
do not use the product: otherwise, this can lead to fire or
electric shock.
(9) If the power connector or the connector of the power cable
becomes dirty or dusty, wipe it with a dry cloth. Otherwise,
this can lead to fire.
(10) PDP Module uses a high voltage (Max.450V dc). Keep
the cautions concerning electric shock and do not touch
the Device circuitry when handling the PDP Unit. And
because the capacitor of the Device circuitry may remain
charged at the moment of Power OFF, standing by for 1
minute is required in order to touch the Device circuitry.
¥–. CAUTIONS
(1) Do not place this product in a location that is subject to
heavy vibration, or on an unstable surface such as an
inclined surface. The product may fall off or fall over,
causing injuries.
(2) Before disconnecting cable from the product, be sure to
turn off the power. Be sure to hold the connector when
disconnecting cables. Pulling a cable with excessive force
may cause the core of the cable to be exposed or break
the cable, and this can lead to fire or electric shock.
(3) This product should be moved by two or more persons. If
one person attempts to carry this product alone, he/she
may be injured.
(4) This product contains glass. The glass may break, causing
injuries, if shock, vibration, heat, or distortion is applied to
the product.
(5) The temperature of the glass of the display may rise to
80°C or more depending on the conditions of use.
If you touch the glass inadvertently, you may be burned.
(6) If glass surface of the display breaks or is scratched, do
not touch the broken pieces or the scratches with bare
hands. You may be injured.
(7) PDP Module requires to be handled with care not to be
touched with metal or hard materials, and must not be
stressed by heat or mechanical impact.
(8) There are some exposed components on the rear panel of
this product. Touching these components may cause an
electric shock.
(9) When moving the product, be sure to turn off the power
and disconnect all the cables. While moving the product,
watch your step. The product may be dropped or all,
leading to injuries of electric shock.
SAFETY PRECAUTIONS

(10) In order to protect static electricity due to C-MOS circuitry of
the Drive part, wear a wrist band to protect static electricity
when handling.
(11) If cleaning the Panel, wipe it with a soft cloth moistened with
water or a neutral detergent and squeezed, being careful not
to touch the connector part of the Panel. And don’t use
chemical materials like thinner or benzene.
(12) If this product is used as a display board to display a static
image, “image sticking” occurs. This means that the luminance
of areas of the display that remain lit for a long time drops
compared with luminance of areas that are lit for a shorter
time, causing uneven luminance across the display.
The degree to which this occurs is in proportion to the
luminance at which the display is used. To prevent this
phenomenon, therefore, avoid static images as much as
possible and design your system so that it is used at a low
luminance, by reducing signal level difference between bright
area and less bright area through signal processing.
(13) Because PDP Module emits heat from the Glass Panel part
and the Drive circuitry, the environmental temperature must
not be over 40°C.
The temperature of the Glass Panel part is especially high
owing to heat from internal Drive circuitry. And because the
PDP Module is driven by high voltage, it must avoid
conductive materials.
(14) If inserting components or circuit board in order to repair, be
sure to fix a lead line to the connector before soldering.
(15) If inserting high-power resistor(metal-oxide film resistor or
metal film resistor) in order to repair, insert it as 10mm away
as from a board.
(16) During repairs, high voltage or high temperature components
must be put away from a lead line.
(17) This is a Cold Chassis but you had better use a cold
transformer for safety during repairs. If repairing electricity
source part, you must use the cold transformer.
(18) Do not place an object on the glass surface of the display.
The glass may break or be scratched.
(19) This product may be damaged if it is subject to excessive
stresses (such as excessive voltage, current, or temperature).
The absolute maximum ratings specify the limits of these
stresses.
(20) The recommended operating conditions are conditions in
which the normal operation of this product is guaranteed. All
the rated values of the electrical specifications are guaranteed
within these conditions.
Always use the product within the range of the recommended
operating conditions. Otherwise, the reliability of the product
may be degraded.
(21) This product has a glass display surface. Design your
system so that excessive shock and load are not applied to
the glass. Exercise care that the vent at the corner of the glass
panel is not damaged.
If the glass panel or vent is damaged, the product is
inoperable.
(22) Do not cover or wrap the product with a cloth or other
covering while power is supplied to the product.
(23) Before turning on power to the product, check the wiring of
the product and confirm that the supply voltage is within the
rated voltage range. If the wiring is wrong or if a voltage
outside the rated range is applied, the product may
malfunction or be damaged.
(24) Do not store this product in a location where temperature
and humidity are high. This may cause the product to
malfunction. Because this product uses a discharge
phenomenon, it may take time to light (operation may be
delayed) when the product is used after it has been stored for
a long time. In this case, it is recommended to light all cells for
about 2 hours (aging).
(25) This product is made from various materials such as glass,
metal, and plastic. When discarding it, be sure to contact a
professional waste disposal operator.
(26) If faults occur due to arbitrary modification or disassembly,
LG Electronics is not responsible for function, quality or other
items.
(27) Use of the product with a combination of parameters,
conditions, or logic not specified in the specifications of this
product is not guaranteed. If intending to use the product in
such a way, be sure to consult LGE in advance.
(28) Within the warranty period, general faults that occur due to
defects in components such as ICs will be rectified by LGE
without charge. However, IMAGE STICKING due to
misapplying the above (12) provision is not included in the
warranty. Repairs due to the other faults may be charged for
depending on responsibility for the faults.
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[PDP42V5#### Module]
CONTENTS
¥ . Formation and Specification of Module
¥–. Adjustment
¥†. Trouble Shooting
1. Checking for No Picture
2. Hitch Diagnosis Following Display Condition
2-1. 4/7 or 3/7 of the screen doesn’t be shown
2-2. Screen doesn’t be shown as Data COF
2-3. It is generated unusual pattern of Data COF IC unit
2-4. Regular Stripe is generated about the quantity of one Data COF IC or more
2-5. Screen doesn’t be shown at all as scan COF
2-6. Regular stripe is generated at regular internal on the whole screen
2-7. Data copy is generated to stripe direction
2-8. One or more stripe is generated on the screen
2-9. One or more horizontal line is generated on screen
2-10. Lightness of screen is wholly darken though there is input-signal-pattern
2-11. Different color is shown partially during full-white-screen or electric discharge is generated
during full-black-screen
2-12. Full-white pattern it happened that the lightness of middle is darken while full-white pattern
2-13. Some lightness of some color doesn’t not generated well
¥‡. Block Diagram
¥·. Records of Revision for Board and EPROM
* Annexing : Schematic Diagram

¥. Formation and Specification of Module
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External Cable Connection
NO
1
2
3
4
5
6
7
Part No.
6871QCH025A
6871QCH029A
6871QDH051A
6871QDH052A
6871QRH034A
6871QYH027A
6871QZH030A
PWB(PCB) ASSY
PWB(PCB) ASSY
PWB(PCB) ASSY
PWB(PCB) ASSY
PWB(PCB) ASSY
PWB(PCB) ASSY
PWB(PCB) ASSY
Description
TMDS CTRL B/D ASSY
LVDS CTRL B/D ASSY
Y DRV UPPER B/D ASSY
Y DRV LOWER B/D ASSY
X RIGHT B/D ASSY
Y SUS B/D ASSY
Z SUS B/D ASSY
NO
1
2
3
4
Connector
P1[Z SUS B/D]
P5[Y SUS B/D]
P6[Y SUS B/D]
P21, P31[CTRL B/D]
Input Signal
5V, Va, Vs
5V, Vs
5V
Video Signal

- 6 -
1. Application Object
This standard is applied to the PDP42V5#### PDP Module
which is manufactured by the manufacturing team of PDP
promotion department or elsewhere.
2. Notes
(1) Without any special specification, the Module should be at
the condition of preliminaries more than 10minutes before
adjusting.
- Service signal : 100% Full White signal
- Service DC voltage : Vcc:5V, Va:65V, Vs:190V
- DC/DC Pack voltage : Vsetup:220V, Vscw:115V,
-Ve:-35V, -Vy:-75V
- Preliminaries environment : Temp (25!5°C), Relative
humidity (65!10%)
(2) Module should get the Aging for the equilibrium after finish
the assembling. Aging condition is shown below.
- Service signal: 100% Full White, Red, Green, Blue pattern
signal(Service time of each pattern : within 5minutes/cycle)
- Service DC voltage : Match the voltage with the set up
voltage in the first adjustment.
- Aging time : More than 4Hrs
- Aging environment : Temp (60!2°C), Relative humidity-
Less than 75%
(3) Module adjustment should be followed by below sequence.
- Setting up the initial voltage and adjusting the voltage
wave form of Vsetup
- Measuring the Margin of Vs voltage and deciding the voltage
- Adjusting and checking the voltage of DC/DC pack
(Vsetup, Vscw, -Ve, -Vy)
- Adjusting the voltage wave form of Vset-down
- Measuring the voltage margin of Vset-up and deciding
the voltage
- Adjusting the wave form of final voltage
But, these items above can be changed by the
consideration of mass production. (When changing the
sequence, there should be an agreement of the Module
development 2Gr/ QA Gr/ Manufacturing Gr)
(4) Without any special specification, you should adjust the
Module in the environment of Temp (25!5°C) and Relative
humidity (65!10%)
Caution) If you let the still image more than 10 minutes(especially
The Digital pattern or Cross Hatch Pattern which has
clear gradation), after image can be presented in the
black level part of screen.
3. Adjustment items
3-1. Adjusting the Board Group
(1) Adjusting the voltage wave form of Vset-up
(2) Adjusting the voltage wave form of Vset-down
(3) Adjusting the voltage wave form of Vramp
3-2 Adjustment after assembling
(PDP Module adjustment)
(1) Setting up the initial voltage and adjusting the voltage
wave form of Vsetup
(2) Measuring the voltage Margin of Vs and deciding the voltage
(3) Adjusting and checking the voltage of DC/DC pack
(Vsetup, Vscw, -Ve, -Vy)
(4) Adjusting the voltage wave form of Vset-down
(5) Measuring the voltage Margin of Vset-up and deciding the
voltage
(6) Adjusting the wave form of final voltage
4. Adjusting the Board Group
(Applying the Jig Set)
4-1. Using Tools
(1) Digital oscilloscope : More than 200MHz
(2) DVM(Digital Multimeter) : Fluke 87 or similar one
(3) Signal generator : VG-825 or similar one
(4) DC power supply
- DC power supply for Vs (1) : Should be changeable more
than 0-200V/ more than 10A
- DC power supply for Va (1) : Should be changeable more
than 0-100V/ more than 5A
- DC power supply for 5V (1) :Should be changeable more
than 0-10V/ more than 10A
- DC-DC Convertor Jig (1) : The Jig which has voltage
equivalent output of PDP42V5#### Module after taking
the Vs, Va, 5V voltage
- Voltage stability of power supply : Within !1% for Vs/Va,
within !3% for 5V
4-2. Connection diagram of measuring
instrument and setting up the initial
voltage
(1) Connection diagram of measuring instrument
Refer to Fig. 1.(Connection diagram of measuring
instrument that adjusting the voltage wave form)
(2) Setting up the initial voltage
Initially setting up voltage : Vcc:5V, Va:65V, Vs:190V
But, Initially setting up voltage can be changed by the set
up range according to the Module’s characteristic.
4-3. How to Adjust
(1) Adjusting the Voltage Wave form of Vsetup
¤Connect measuring instrument like the connection
diagram Fig. 1.
¤ŁTurn on the power of the measuring instrument like the
<Caution> item Fig. 1.
¤ØConnect the oscilloscope probe to P4 connector(80 Pin)
of Y-SUS PCB and GND.
¤Œ Turn the VR1 of Y-SUS PCB and make the “A“ wave
form Fig. 2 to be 25!5µs.
(2) Adjusting Vset-down Voltage Wave form
Turn the VR2 of Y-SUS PCB and make the “B” wave form
Fig. 2 to be 190!5µs.
(3) Adjusting Vramp Voltage Wave form
¤Connect oscilloscope Probe to the B37(Pin) of Z PCB
and the GND of PCB
¥–. Adjustment

- 7 -
¤ŁTurn the VR3 of Z PCB and make the “C” wave form Fig.
3 to be 15!2µs.
But, in case of not setting up the Test point, produce
same output and adjust wave form connect to other
pattern or parts which has no possibility of short.
5. Adjustment after Assembling
(PDP Module Adjustment)
5-1. Using Tools
(1) Digital oscilloscope : More than 200MHz
(2) DVM(Digital Multimeter): Fluke 87 or similar one
(3) Signal generator: VG-825 or similar one
(4) DC power supply
- DC power supply for Vs (1) : Should be changeable more
than 0-200V/ more than 10A
- DC power supply for Va (1) : Should be changeable more
than 0-100V/ more than 5A
- DC power supply for 5V (1) : Should be changeable more
than 0-10V/ more than 10A
- DC-DC Converter Jig (1) : The Jig which has voltage
equivalent output of PDP42V5#### Module after taking
the Vs, Va, 5V voltage
- Voltage stability of power supply : Within !1% for Vs/Va,
within !3% for 5V
5-2. Connection diagram of measuring
instrument and setting up the initial
voltage
(1) Connection diagram of measuring instrument
Refer to figure 1. (Connection diagram of measuring
instrument that adjusting the voltage wave form)
(2) Setting up the initial voltage
Initially setting up voltage : Vcc:5V, Va:65V, Vs:190V
But, Initially setting up voltage can be changed by the set
up range according to the Module’s characteristic.
5-3. How to Adjust
(1) Adjusting initial voltage wave form
Check the voltage wave form like the mentioned way on
the 4-3(How to adjust) and readjust the wave form when it
is wrong.
(2) Checking the DC/DC pack voltage
¤Convert the signal of signal generator to the 100% Full
White signal
¤ŁConnect the GND terminal of DVM to the GND of Y B/D
and set the Plus terminal to the right up leg of R9 to
check the -Ve voltage(-35!1V). And when there is
abnormality in voltage turn the variable resistor(VR7) of
DC/DC Pack(-Ve) on Y B/D to adjust.
¤Ø Connect the GND terminal of DVM to the R60’s right leg
of the Y B/D and set the Plus terminal to the left leg of
R60 to check the Vscw voltage(115!1V) and when there
is abnormality in voltage turn the variable resistor(VR5)
of DC/DC Pack(Vscw) on Y B/D to adjust.
¤Œ Connect the GND terminal of DVM to the R8’s right leg
of the Y B/D and set the Plus terminal to the left leg of
R8 to check the -Vy voltage(-80!1V) and when there is
abnormality in voltage turn the variable resistor(VR6) of
DC/DC Pack(-Vy) on Y B/D to adjust.
¤º Connect the GND terminal of DVM to the R89’s right leg
of the Y B/D and set the Plus terminal to the left leg of
R89 to check the Vsetup voltage(240!1V) and when
there is abnormality in voltage turn the variable
resistor(VR4) of DC/DC Pack(Vsetup) on Y B/D to adjust.
(3) Measuring the Vs voltage Margin and deciding
the voltage
¤Convert the signal of signal generator to the 100% Full
Red signal.
¤ŁTurn the voltage adjusting knob of Vs DC power supply
to the voltage -down direction and make the cell of
screen turned off.
¤Ø Turn the voltage adjusting knob of Vs DC power supply to
the voltage -up direction until the cell of screen turned on.
The first voltage, which make the cell of full screen
turned on, is named as Vsmin1 and record it.
¤Œ Turn the voltage adjusting knob of Vs DC power supply
to the voltage-up direction slowly until the cell of screen
turned off or over electric discharge.
The first voltage, which makes the cell of screen turned
off or over electric discharge, is named as Vsmax1 and
records it. (Only, Vs voltage variable passes over the
maximum 195V)
¤º Convert the signal of signal generator to the 100% Full
Green signal.
¤Repeat the adjustment (2) item and name each voltage
as Vsmin2/Vsmax2 and record them.
¤Convert the signal of signal generator to 100% Full Blue
signal.
¤Repeat the adjustment (2) item and name each voltage
as Vsmin3/Vsmax3 and record them.
¤Convert the signal of signal generator to 100% Full
White signal.
¤Repeat the adjustment (2) item and name each voltage
as Vsmin4/Vsmax4 and record them.
(Fig. 2) Y Set-up Wave form
wave form
(Fig. 3) Z ramp Wave form
190±5µs

- 8 -
¤æ Convert the signal of signal generator to 100% Full Black
signal.
¤Repeat the adjustment (2) item and name each voltage as
Vsmin5/Vsmax5 and record them.
¤At this time decided Vs voltage (Vsmin1-Vsmin5)adds 6V to
Max value and set up the voltage within the set-up
range(180V < Vs #195V) in consideration of other
features.
¤Turn the voltage adjusting knob of Vs DC power supply
make deciding the Vs voltage.
¤ı Adjust Vset down wave form using setting up Vs voltage
like mentioned on the 4-3.
(4) Adjusting the final voltage wave form
Check the voltage wave form like the mentioned way on the 4-
3(How to adjust) and readjust the wave form when it is twisted.
(5) DC-DC Pack Voltage Set up Range
Vsetup : 210V ~ 240V
Vsc : 90V ~ 120V
-Vy : -60V ~ -80V
-Ve : -35V ~ -45V

- 9 -
190 1.0 voltage
65 0.1 voltage
5 2.5 voltage
(VG-825 ) Àü¿ø
Y - SUS
CONTROLLER
Z - SUS
E/X Tube
X right
190 1.0 voltage 190 1.0 voltage
65 0.1 voltage
5 2.5 voltage 5 2.5 voltage
(VG-825 )
Y - SUS
CONTROLLER
Z - SUS
E/X Tube
X right
Y - SUS
CONTROLLER
Z - SUS
E/X Tube
X right
Signal Generator Power
DC Power Supply for 5V
DC Power Supply for Va
DC Power Supply for Vs
<Caution>
(1) The power of the signal generator should be turned on before turning on the power of DC power supply.
(2) The voltage of DC power supply , in standard of Module input voltage, should be preset as below.
Vcc: 5V, Va: 65V, Vs: 190V
(3) The power of power supply must turned on by this sequence. Reverse direction When turning off.
* Module on : 5V
( Va ( Vs, Module off: Vs ( Va ( 5V
(4) Signal generator should be selected with 852*480 mode(WVGA)
(Fig. 1) Connection diagram of measuring instrument

- 10 -
1. Checking for no Picture
A screen doesn¡flt display at all and condition of black pattern or power off.
(1) Check whether the CTRL B/D LED(D1~D4) is turned on or not.
(2) Check the power and signal cable of CTRL B/D.
(3) X B/D, Y B/D, Z B/D is well plugged in.
(4) Check the connection of X B/D, Y B/D and Z B/D to CTRL B/D.
(5) Measure the output wave of X, Y, Z B/D with oscilloscope(more than 200MHz)
and find the trouble of B/D by comparing the output wave with below figure.
- Measure Point fo Y B/D : TP (Connector P4 80 pin)
- Measure Point fo Z B/D : Connection part of panel (SUS_OUT)
- Measure Point fo X B/D : L1(RIGHT), L2(LEFT BOTTOM)
(6) Check the SCAN(Y side) IC
(7) Check the DATA(X side) COF IC
(8) Replace the CTRL B/D.
<A : Y B/D Output wave - 1FRAME>
<B : Y B/D Output wave - 1 SF>
¥†. Trouble Shooting

- 11 -
<A : Y B/D Output wave - 1Frame>
<B : Y B/D Output wave - 7~12 SF>
<A : Z B/D Output wave - 1Frame>
<B : Z B/D Output wave - 1SF>
<X B/D Output wave - 1 FRAME>
<X B/D Output wave - 1 SF>
<X B/D Output wave - Enlargement>

2. Hitch Diagnosis Following
Display Condition
2-1. 4/7 or 3/7 of the screen doesn’t be
shown
(1) Confirm the power connector of X B/D is well plugged in
which is correspond to not showing screen.
(2) Confirm the connector that is connected between CTRL
B/D and X B/D correspond to not showing part.
(3) Replace relevant X B/D.
[[Relationship between screen and X B/D
Screen X B/D
Left of the Screen 4/7 <--> Right X B/D
Right of the Screen 3/7 <--> Left X B/D
[[Screen Display Form
2-2. The screen doesn’t be shown as Data
COF
(Include not be shown part of Data COF quantity or a part)
(1) The problem between Data COF and X B/D is more
possible that the screen is not be shown as data COF.
(2) Confirm the connector of Data COF is well connected to X
B/D. Correspond to the part that screen is not showing
(3) Confirm whether the Data COF is failed and replace X B/D
[[Example of the screen display form
(Anything of the 7 Data COF can be shown beside below
pictures)
: All
: Partial
: not at all
ANODE Pattern (GND)
CATHOD Pattern and examine the Diode
to the pure or reverse direction.
1
GND
1
Measure the third resistance value
Resistance
2
2
- 12 -
[[How to examine Data COF IC
Left of the Screen(4/7) Right of the Screen(3/7)
Display
Not display

2-3. It Generates Unusual Pattern of Data
COF IC unit
(1) In case of generating unusual pattern of Data COF IC unit
as below picture, there is problem in the check that is input
into Data COF IC
(2) In case of <case 1, 2, 3>
- confirm the connection of Data COF connector
- replace the relevant X B/D
(3) In case of <case 4, 5>
- confirm the connector that is connected from CTRL to X B/D
- Replace relevant XB/D or CTRL B/D
[[Screen Display Form
2-4. Regular Stripe is Generated about the
Quantity of one Data COF IC or more
(1) In case of generating regular stripe about the quantity of
one Data COF IC, there is problem at the output of output-
flatworm of X B/D
In case of generating regular stripe about the quantity of
two Data COF IC, that means the data which is conveyed
from CTRL B/D doesn’t conveyed well.
(2) Confirm the XB/D connection connector plugged in well.
Correspond to unusual screen.
(3) Replace relevant XB/D or CTRL B/D.
[[Relationship between screen and X B/D
Screen X B/D
Left Bottom of the Screen 4/7 <--> Right X B/D
Right Bottom of the Screen 3/7 <--> Left X B/D
[[Screen Display Form
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<Case 1>
<Case 2>
<Case 3>
<Case 4>
<Case 5>
Unusual screen comes out
about one IC quantity in
one COF
Unusual screen comes out
across one quantity about
two IC quantities in one
COF
Unusual screen comes out
about 4IC quantities in
one COF
Unusual screen comes out
as a unit of Data COF IC
through one X B/D
Unusual screen comes out
as a unit of Data COF IC
through Top or Bottom
screen
It comes out partial field about
the quantity of one IC or more
or It may come out together
at other field of screen.

2-5. The screen display has a problem for
Scan FFC.
(1) It’s may be a problem between Scan FFC and Y B/D.
(2) Check the connection of Y B/D and Scan COF.
(3) If the Scan IC is failed, replace the Y DRV B/D.
[[Screen Display Form
[[Check a method of SCAN IC
Change the Vpp Pin into ANODE and GND Pin into CATHOD
and then test the Diode with forward or reverse direction.
2-6. The screen has a vertical line with
regular gap.
(A vertical stripe flash at especial color)
(1) This is a problem about control B/D.
(2) Replace Control B/D.
[[Screen Display Form
2-7. A data copy is happened into vertical
direction
(1) In this case, it’s due to incorrect marking of scan wave.
(2) Replace a Y DRV B/D or Y SUS B/D.
[[Screen Display Form
- 14 -
one eighth
of screen
The screen display is very good
The screen display is a poor
The screen has a vertical line
with regular gap
<Case 1 : Entire Copy><Display Pattern>
<Case 2 : Top Copy> <Case 3 : Bottom Copy> <Case 4 : Entire Copy>

2-8. The screen has one or several vertical
line
(1) In this case, It isn’t a problem about controller B/D or X
B/D.
(2) It may cause followings.
- It’s out of order a panel
- Open or short of DATA COF FPC attached panel
- It’s out of order a DATA COF attached panel
(3) Replace Module.
[[Screen Display Form
2- 9. The screen has one or several
horizontal line
(1) In this case, it isn’t a problem about controller B/D or X
B/D.
(2) It may cause followings.
- It’s out of order a panel
- Open or short of SCAN FPC attached panel
- It’s out of order a SCAN IC attached panel
(3) Replace Y DRV B/D
[[Screen Display Form
2-10. The screen displays input signal
pattern but the brightness is dark
(1) In this case, Z B/D operation isn’t complete.
(2) Check the power cord of Z B/D.
(3) Check the connector of Z B/D and Controller B/D.
(4) Replace the Controller B/D or Z B/D.
2-11. The screen displays other color
partially on full white screen or happens
discharge partially on full black screen.
(1) Check the declination of Y B/D set up, set down wave.
(2) Check the declination of Z B/D ˙ramp wave.
(3) Measure each output wave with oscilloscope(more than
200MHz) and compare the data with below figure data.
Adjust the Y B/D set up(Test-up:B/C[¥s/¥s])/setdown(Test-
down:D[¥s]) and Z B/D ramp(Tramp:F/G[¥s/¥s]) declination
by changing VR1/VR2/VR3.
- Measuring Point of Y B/D : P4 (Connector P4 36 pin)
- Measuring Point of Z B/D : B37 (SUS_OUT)
2-12. A center of screen is darker than
a edge of screen at full white pattern.
(1) In this case, it’s a problem about Z B/D ramp wave.
(2) Check the connection cable of Z B/D and CTRL B/D.
(3) Replace the Z B/D.
[[Screen Display Form
2-13. It doesn’t display a specified
brightness at specified color
(1) Check the connector of CTRL B/D input signal.
(2) Replace the CTRL B/D.
- 15 -
It may show several vertical
lines in a quarter or other
division part of screen
including left case.
It may show several horizontal
lines including left case.
Y Output Voltage Wavefrom Z RAMP Voltage Wavefrom

- 16 -
¥‡. Block Diagram

- 17 -
¥·. Records of Revision for Boards and ROM DATA
1. Board
No.
1
2
3
4
5
6
7
Date
2003.04.21
2003.04.21
2003.04.21
2003.04.21
2003.04.21
2003.04.21
2003.04.21
Part Number
6871QCH025A
6871QCH029A
6871QDH051A
6871QDH052A
6871QYH027A
6871QZH030A
6871QRH034A
Note
Initial Product
Initial Product
Initial Product
Initial Product
Initial Product
Initial Product
Initial Product
Board
CTRL B/D ASSY(TMDS)
CTRL B/D ASSY(LVDS)
YDRV Upper B/D ASSY
YDRV Lower B/D ASSY
Y SUS B/D ASSY
Z SUS B/D ASSY
X RIGHT B/D ASSY

- 18 -
2. ROM DATA
No.
1
2
Date
2003.04.21
2003.04.21
Contents
Initial ROM Data of TMDS
Initial ROM Data of LVDS
ROM Data Version
42V5_06
42V5_08

June, 2003
Printed in Korea3828VD0143E