Dynex DX-26LD150A11 Schematic

Distributed by Xiamen Overseas Chinese Electronic Co.,LTD (XOCECO)

SERVICE MANUAL

Product Type: LCD TV Chassis: KS Chassis Manual Series:

Manual Part#: 9226KS7010

Model Line: Product Year:

Product Safety Servicing Guidelines....................................................................................1

Remote Control Unit.............................................................................................................2

Main Unit (Front View/Side View/Rear View)........................................................................3

Specifications......................................................................................................................4

Alignment Instructions..........................................................................................................5

Software Upgrade Instructions...........................................................................................11

Working principle analysis of the unit................................................................................15

Block Diagram....................................................................................................................16

Troubleshooting Guides.....................................................................................................17

Wiring Diagram..................................................................................................................22

Schematic Diagram............................................................................................................23

Printed Circuit board layouts..............................................................................................28

Exploded View Parts List....................................................................................................30

CONTENTS

Product Safety Servicing Guidelines

Temperature

Scope for operation

0 ~ +50 oC

Scope for storage -20 ~ +60 oC

Humidity Scope for operation 20% ~ 85%

Scope for storage 10% ~ 90%

ATTENTION: This service manual is only for service personnel to take

reference with. Before servicing please read the following points carefully.

CAUTION: Do not attempt to modify this product in any way.

Ne v er pe r form cu sto m ize d insta l lat i ons wi thou t manufacturer’s approval. Unauthorized modifications will not only void the warranty, but may lead to property damage or user injury.

Service work should be performed only after you are thoroughly familiar with these safety checks and servicing guidelines.

GRAPHIC SYMBOLS

The exclamation point within an equilateral triangle is intended to alert the service personnel to important safety information in the service literature.

The lightning flash with arrowhead symbol within an equilateral triangle is intended to alert the service person ne l to the pre sence of noni ns ulated “dangerous voltage” that may be of sufficient magnitude to constitute a risk of electric shock.

6. Should there be smoke, abnormal smell or sound from the module, please shut the power off at once. Likewise, if the screen is not working after the power is on or in the course of operation, the power must be cut off immediately and no more operation is allowed under the same condition.

7. Do not pull out or plug in the connection wire when the module is in

operation or just after the power is off because in this case relatively high voltage still remains in the capacitor of the driving circuit. Please wait at least one minute before the pulling out or plugging in the connection wire.

8. When operating or installing LCD please don't subject the LCD

components to bending, twisting or extrusion, collision lest mishap should result.

9. As most of the circuitry in LCD TV set is composed of CMOS

integrated circuits, it's necessary to pay attention to anti statics. Before servicing LCD TV make sure to take anti static measure and ensure full grounding for all the parts that have to be grounded.

10.There are lots of connection wires between parts behind the LCD

screen. When servicing or moving the set please take care not to touch or scratch them. Once they are damaged the screen would be

unable to work and no way to get it repaired. If the connection wires, connections or components fixed by the thermotropic glue need to disengage when service, please soak the thermotropic glue into the alcohol and then pull them out in case of damage.

11.Special care must be taken in transporting or handling it. Exquisite

shock vibration may lead to breakage of screen glass or damage to

driving circuit. Therefore it must be packed in a strong case before

the transportation or handling.

12.For the storage make sure to put it in a place where the environment

can be controlled so as to prevent the temperature and humidity from exceeding the limits as specified in the manual. For prolonged storage, it is necessary to house it in an anti-moisture bag and put them altogether in one place. The ambient conditions are tabulated as follows:

INSTRUCTIONS

Be sure to switch off the power supply before replacing or welding any components or inserting/plugging in connection wire. Anti static measures must be taken (throughout the entire production process!): a) Do not touch here and there by hand at will; b) Be sure to use anti static electric iron; c) It's necessary for the welder to wear anti static gloves. Please refer to the part list before replacing components that have special safety requirements. Do not replace with different components with different specs and type at will.

13. Display of a fixed p ict ure for a lo ng t ime may result in app e a r a n ce o f p i c t u r e r e s i due o n t h e sc r e e n , a s commonly c all ed “g hos t shadow”. Th e ext ent of the residual picture v ari es wi th th e maker of LCD screen.

LCD SERVICING PRECAUTIONS

1. Screens are different from one model to another and therefore not interchangeable. Be sure to use the screen of the original model for replacement.

2. The operation voltage of LCD screen is 700-825V. Be sure to take proper measures in protecting yourself and the machine when testing the system in the course of normal operation or right after the power is switched off. Please do not touch the circuit or the metal part of the module that is in operation mode. Relevant operation is possible only one minute after the power is switched off.

3. Do not use any adapter that is not identical with the TV set. Otherwise it will cause fire or damage to the set.

4. Never operate the set or do any installation work in bad environment such as wet bathroom, laundry, kitchen, or nearby fire source, heating equipment and devices or exposure to sunlight etc. Otherwise bad effect will result.

5. If any foreign substance such as water, liquid, metal slices or other matters happens to fall into the module, be sure to cut the power off immediately and do not move anything on the module lest it should cause fire or electric shock due to contact with the high voltage or short circuit.

This phenomenon doesn't represent failure. This “ghost shadow” may rema in in the picture for a per iod of time (several minutes). But wh en ope rat ing it please avoid displaying still picture in high brightness for a long time.

Points for attention during installation

1. The fr ont pane l of LCD sc ree n is of glass. W hen installing it please make sure to put it in place.

2. For service or ins tal lat ion it' s ne ces sar y to use specified screw lest it should damage the screen.

3. Be sure to take anti dust measures. Any foreign substance that hap pen s to fa ll do wn between the screen and the glass will affec t the r ece ivi ng an d vie win g effect

4. W hen di sma ntl ing or mounting t he protective par tit ion plate t hat is u sed for ant i vibration an d insulation p lea se take ca re to kee p it in intactness so as to avoid hi dde n trouble.

5. Be su re to protect the c abi net from dam age o r scratch during service, dismantling or mounting.

Remote control

Remote Control Unit

INPUT POWER

RECALL

MUTE

VOL+/VOL–

VIDEO/HDMI/TV COMP/VGA

Press to open the on-screen menu.

Press to turn off the sound. Press again to turn on the sound.

Press to increase or decrease the volume.

Press to select the input source.

• Press VIDEO once to select AV1, twice to select AV2, three times to select S-Video1, and four times to select S-Video2.

• Press HDMI once to select HDMI1, twice to select HDMI2, and three times to select

INFO

GUIDE

HDMI3.

! Press TV to select TV. ! Press COMP once to select Component1

or twice to select Component2.

! Press VGA to select VGA.

VOL+

VOL- CH

ENTER

MUTE

FAVOR IT E

EXIT

SLEEP

ZOOM

PICTURE

Press to set the sleep timer.

Press to select the aspect ratio.

Press to select the picture mode.

VIDEO

COMP

ZOO M

HDMI

MTS/SAP

SLEEP

VGA

CH-LIST

RECALL

GUIDE

Press to go to the last viewed channel.

Press to open the DTV program guide (if available).

PICTURE

INPUT

Numbers/Dot(.)

INFO

AUDIO

CCD

Press to turn on your TV. Press again to put your TV in Standby mode. Press to open the INPUT SOURCE menu,

then press 5 or 6 to select the video input source.

Press to enter channel numbers or the parental control password. Press the dot button to select a digital sub-channel.

Press to display the information banner.

Press direction buttons to navigate in the onscreen menus. Press ENTER to confirm selections in an on-screen menu or to open a submenu.

EXIT

CH /CH

FAVORITE

MTS/SAP

CH-LIST

CCD

AUDIO

Press to close the on-screen menu.

Press to go to the next or previous channel in the channel list.

Press to display the favorite channel list.

Press to select the audio mode. For analog channels, you can select STEREO, SAP (secondary audio program), or MONO. For digital channels, you can select the audio track (if more than one track is available).

Press to open the channel list.

Press to turn closed captioning on or off.

Press to select the sound mode.

Main Unit (Front View/Side View/Rear View)

SERVI CE PORT

HDMI 2

AUDIO

AV2 IN

VIDEO

DIGITAL OUTPUT

jack

HDMI1 jack

PC IN VGA/AUDIO jacks

S-VIDEO/AV1 IN jack

B R

PC IN

VGA

Connect this jack to a digital sound system to play your TV’s audio through the sound system. For more information, see “Connecting a digital sound system” on page 10.

Connect an HDMI device, such as a cable box or DVD player, to the jack. An HDMI cable carries both video and audio, so you do not need to mak e an audio connection. For more information, see “Connecting an HDMI device” on page 9.

Connect a computer to these jacks. For more information, see “Connecting a computer” on page 10.

Connect an AV or S-Video device to these jacks, then connect audio cables to the audio jacks.

ANT/ CA BLE IN

AUDIO OUT jack

COMPONENT IN jacks

ANT/CABLE IN jack

AV2 IN jack

HDMI2 jack

Headphone jack

SERVICE PORT

Connect an audio amplifier to these jacks.

Connect a component video device to these jacks. For more information, see “ Connecting a component video device” on page 9.

Connect an antenna, cable TV, or a satellite box to this jack. For more information, see “Connecting an antenna, cable TV, or satellite TV box” on page 8.

Connect an AV device (video and audio) to these jacks. Match the color of the connectors to the color of the jacks (yellow for video, red for audio right, and white for audio left).

Connect an HDMI device, such as a cable box or DVD player, to this jack.

Plug headphones into this jack.

For software update only. Do not use.

SPECIFICATIONS

26” TF T LCD

NTSC-M, ATSC

VHF: 2-13 UHF: 14-69 CATV: 1-125 CADTV: 1-135 DTV: 2-69

5 W x 2

85 W

646 x 462 x 256 mm (Stand included)

8.2 kg (Stand included)

Audi o left an d right ( 1) Digi tal out put (1) Head phone j ack (1)

Note:

1. Design and specifications are subject to change without notice.

2. Weight and dimensions shown are approximate.

3. Specifications and external appearance may be changed for the sake of improvement.

ALIGNMENT INSTRUCTIONS

1. Test equipment

VG848 (YPbPr, VGA signal generator) VG849 (HDMI signal generator) CA210 (color analyzer)

2. Alignment procedure

2.1 Connect all the boards according to wiring diagram. Connect the power supply and presss “standby” to turn on the TV.

2.1.1 For 32” /37” /42”/46” model a) In turn measure X508 all pins voltage on Power Board, the value is shown below (Table 1):

Table 1 X508 all pin voltage Pin 1 2 3 4, 5 6, 7 8 9 10 11 12 13 Min.(V) 4.85 3.25 0 11.3 0 0 4.85 0 4.85 0 2.85 Typical(V) 5.00 3.30 0 12.0 0 0 5.00 0 5.00 0 3.00 Max.(V) 5.35 3.30 0 12.6 0 0 5.35 0 5.35 0 3.15

b) In turn measure X505 all pins voltage on Power Board, the value is shown below (Table 2):

Table 2 X505 all pin voltage Pin 1, 2 3, 4, 5 Min.(V) 23.8 0 Typical(V) 24.0 0 Max.(V) 25.2 0

c) In turn measure X503 all pins voltage on Power Board, the value is shown below (Table 3):

Table 3 X503 all pin voltage Pin 1～5 6～10 11 12

Min.(V) 23.8 0 3.25 4.85

Typical(V) 24.0 0 3.30 5.0

Max.(V) 25.2 0 3.30 5.35

2.1.2 For 26” model a) In turn measure X505 all pins voltage on Power Board, the value is shown below (Table 4):

Table 4 X505 all pin voltage Pin 1 2 3 4, 5 6, 7 8 9 10 11 12 13 Min. (V) 4.85 3.25 0 11.3 0 0 4.85 0 4.85 0 2.85 Typical(V) 5.00 3.30 0 12.0 0 0 5.00 0 5.00 0 3.00 Max. (V) 5.35 3.30 0 12.6 0 0 5.35 0 5.35 0 3.15

b) In turn measure X503 all pin voltage on the Power Board, the value is shown below (Table 5):

Table 5 X503 all pin voltage Pin 1, 2 3, 4, 5 Min. (V) 21.6 0 Typical (V) 24.0 0 Max. (V) 26.4 0

c) In turn measure X502 all pin voltage in Main Board, the value is shown below (Table 6):

Table 6 X502 all pin voltage Pin 1～5 6～10 11 12

Min.(V) 21.6 0 3.25 4.85

Typical(V) 24.0 0 3.40 5.0

Max.(V) 26.4 0 3.60 5.35

ALIGNMENT INSTRUCTIONS

2.2 Alignment flow-chart The alignment flow-chart is shown below (Fig. 1) :

Check if DDC, FLASH is written?

Make Data Processing Board

Mounting alignment (Check if the voltage is 120V)

White balance alignment

Input test signal, check TV all performance (such as all programs are searched, analog control, etc.). Check if headphone and speaker output normally.

Input AV/SVIDEO signal, check if the AV jacks perform normally.

Input HD signal, check if YPbPr jacks perform normally.

Input VGA signal, check if the display is normal. Check all

performance (analog control), H-center, V-center, etc.

Input HDMI signal, check if the display is normal. Check all

performance (analog control), H-center, V-center, etc.

Ex-factory preset

Check accessories, packing

Fig.1 Alignment flow-chart

3. Alignment instructions

3.1 The whole unit alignment

3.1.1 According to the wiring diagram, connect Data Process Board, Power Board, Key board, IR Board. Connect AC 120V power and turn on the TV, check if the display is normal.

3.1.2 The way to use Factory Menu a) Press INPUT button, then in turn press “2”, “5”, “8”, “0” to enter the Factory Menu. b) Press CH+ or CH- to select items, then press OK to enter. c) Press CH+ or CH- to move the highlight up or down. d) Press VOL- or VOL+ to adjust the selected item. e) Press MENU to return to the previous menu. f) Press EXIT to close the Factory Menu.

g) After closing the Factory menu, you can press SLEEP to enter the Factory Menu directly if power

is still on.

h) In Factory Menu, select “On” for “Aging Mode” to turn on aging mode. Press any button on the unit

to exit.

i) “Power on mode” item of “Otherseting” has three options: “On” means power on directly; “Off”

means the unit will be in “standby” state when connect the power supply, and needed to press “power” button to turn on; “Memory” means the unit will in the last power-off state after power-on.

3.2 White balance adjustment

3.2.1 Preparations Before white balance adjustment, let the TV work for more than 30 minutes and be in stable status. Use Color Analyzer CA210 BBY channel for alignment. Only align NORMAL color temperature. To ensure both COOL and WARM color temperature to be able to meet the requirements, please make sure bright step color temperature to be △X≤±5,△Y≤±5, dark step color temperature to be

△X≤±5,△Y≤±5. Below table shows the color temperature for all models:

Model Cool Normal Warm

26”/32”/37”/42”/46” 12000K (272,278) 9300K (285,293) 6500K (313,329)

ALIGNMENT INSTRUCTIONS

Table 7 Color temperature for all models

Below white balance adjustment takes 42” model as an example. For other models, use the above data as a reference for alignment.

3.2.2 White balance data alignment at four modes

a) Alignment at ATV mode (AV and S-VIDEO is the same)

In TV mode, set Air/Cable to Air. Input test signal with 11 gray steps. From Factory menu select “Color Temp” item and set “Color Mode” to “NORMAL”, fix GAIN GREEN, adjust GAIN RED and GAIN BLUE to make 9th step color coordinate to be (285, 293). Fix OFFSET GREEN, adjust OFFSET RED and OFFSET BLUE to make the third step color coordinate to be (285,293). In this way repeatedly adjust GAIN RED, GAIN BLUE and OFFSET RED, OFFSET BLUE until two level gray step’s color coordinate be (285,293). Then select “MENU” to return to previous menu or select “SAVE TO EEPROM” to save the white balance.

Check if COOL and WARM color temperature meet the requirement. If not, then adjust GAIN RED, GAIN BLUE, OFFSET RED, OFFSET BLUE to make them meet requirements, and then save.

b) Alignment at DTV mode (HDMI is the same)

Check if COOL and WARM color temperature meet the requirement. If not, then adjust GAIN RED, GAIN BLUE, OFFSET RED, OFFSET BLUE to make them meet requirements, and then save.

c) Alignment at YPbPr mode

First perform ADC calibration: input 75% color bar plus gray step signal in 480i/60Hz format, (VG848 Timing is 968, PAT is 918), enter Factory Menu select ADC Setting, do ADC AUTO adjustment once.

White balance adjustment: From VG848 equipment input 8 gray steps signal in 1920 x 1080i /60Hz format. Enter Factory Menu select “Color Temp”, first set “Color Mode” to NORMAL, fix GAIN GREEN, adjust GAIN RED and GAIN BLUE to make the 7th color coordinate be (285, 293). Fix OFFSET GREEN, adjust OFFSET RED and OFFSET BLUE to make the second step color coordinate be (285,

293). In this way repeatedly adjust GAIN RED, GAIN BLUE and OFFSET RED, OFFSET BLUE until two level gray step color coordinate be (285, 293). Then select “MENU” to return to previous menu or select “SAVE TO EEPROM” to save the white balance.

Check if COOL and WARM color temperature meet the requirement. If not, then adjust GAIN RED, GAIN BLUE, OFFSET RED, OFFSET BLUE to make them meet requirements, and then save.

d) Alignment at VGA mode

First do ADC calibration: input VESA crosshatch signal in 800 x 600 / 60Hz format (VG848 Timing is 854, PAT is 914), check if the picture is displayed wholly. If not, perform AUTO adjustment by making use of VGA Setting sub-menu from SETUP menu (User menu) so that the picture is displayed wholly. Then enter Factory Menu select ADC Setting, do ADC AUTO adjustment once to calibrate ADC.

White balance adjustment: From VG848 equipment input 8 gray steps signal in 800 x 600 /60Hz format. Enter Factory Menu select “Color Temp”, first set “Color Mode” to NORMAL, fix GAIN GREEN, adjust GAIN RED and GAIN BLUE to make the 7th color coordinate be (285, 293). Fix OFFSET GREEN, adjust OFFSET RED and OFFSET BLUE to make the second step color coordinate be (285,

Check if COOL and WARM color temperature meet the requirement. If not, then adjust GAIN RED, GAIN BLUE, OFFSET RED, OFFSET BLUE to make them meet requirements, and then save.

4. Performance check

4.1 TV performance Input RF signal, first enter into CHANNEL menu, then perform Auto Scan to check if all programs can be found, the speaker output normally, picture is displayed normally. Pay special attention that both NTSC and ATSC signals are found.

4.2 Checking AV/S-Video jacks Respectively input signal from AV/S-VIDEO jacks, check if the picture and sound are normal.

4.3 Checking YPbPr/YCbCr jacks Input YUV signal (from VG848 signal generator), respectively input all formats of YUV signal which is shown at below (Table 8) to check if the display and sound are normal.

ALIGNMENT INSTRUCTIONS

Table 8 YUV signal formats

# Resolution

1 720×480i@59.94/60 Hz 15.734 59.94/60 13.5 480i(59.94/60p)

2 720×480p@59.94/60 Hz 31.469 59.94/60 27.00 480p(59.94/60p)

3 1280×720p@59.94/60 Hz 44.96 59.94 74.18 720p(59.94/60p)

H-freq.

(kHz)

V-freq.

(Hz)

Dot-Clk Freq.

(MHz)

Remarks

ALIGNMENT INSTRUCTIONS

4 1920×1080i@59.94/60 Hz 33.75 59.94 74.25 1080i(59.94/60i)

5 1920×1080p@23.98/24 Hz 27.00 23.98/24 74.25 1080p(23.98/24p)

6 1920×1080p@59.94/60 Hz 67.50 60.00 148.50 1080p(59.94/60p)

4.4 Checking VGA jack Input VGA signal (VG848 signal generator)，respectively input all formats of VGA signal which is shown below (Table 9). Check if the display and sound are normal. If the picture has deflection in size and position, then enter into user menu of Setup, from VGA Setting sub-menu perform AUTO adjustment to correct the picture automatically.

Table 9 VGA signal formats

# Resolution H-fre. (kHz) V-fre. (Hz)

720×400@70 Hz 31.47 70.08 28.32 DOS

640×480@60 Hz 31.50 60.00 25.18 VESA

800×600@60 Hz 37.90 60.00 40.00 VESA

1024×768@60 Hz 48.40 60.00 65.00 VESA

1280×1024@60 Hz 63.98 60.02 108.00 Only for 37”/42”/46” model

1360×768@60 Hz 47.71 60.01 85.50 Only for 26” and 32” model

1920×1080@60 Hz 67.16 59.96 173.00 Only for 37”/42”/46” model

Dot-CLK freq. (MHz)

Remarks

4.5 Checking HDMI jack Input HDMI signal (VG849 signal generator), respectively input all formats of signal shown at Table 8. Check if the display and sound are normal.

5 User menu preset Enter into Factory menu, select and do Other Setting→SHIPMENT item, then the TV will automaticlly preset the user menu to default. After alignment this User Menu Preset procedure must be done. SHIPMENT will do the following :

1) Clear all program information

2) Clear V-CHIP information

3) Analog value default setting for all sources

4) Power on mode set to Off

5) Active Setup Wizard menu Note: after the Preset procedure is complete, it must exit the menu, power off at Standby state and then disconnect the power supply.

6. Software writing instructions are shown at below (Table 10)

Table 10 Software writing instructions

# Part No. Model

NS04 5272532005 MX25L3205DM2C-12G

NS03 5272404002 AT24C04IV-10SU-2.7

Software function

Main software

HDCP KEY

Method Remarks

Write with instrument like ALL11. Write-protection is needed.(See below note) Write with instrument like ALL11

For all models

NB01 5272402002 AT24C02BN10SU-1.8 VGA EDID

NA05 5272402002 AT24C02BN10SU-1.8

HDMI1 EDID

Write with instrument like ALL11

For all models

Only for 32”/37”/42”/46” models

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