Changhong Electric LS18 User manual

0
LCD COLOUR TV
MAINTENANCE MANUAL
MODEL: LS18 CHASSIS
（
MSD308/309PX
）
Please read this manual carefully before maintenance
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CATALOG
Chapter1 Safety and notes.........................................................................................................................................................2
1-1 Installation notes ......................................................................................................................................................... 2
1-2Attention points of operation and using ......................................................................................................................2
1-3 Storage notes...............................................................................................................................................................2
1-4 Dismantling notes........................................................................................................................................................2
1-5 High-voltage warning..................................................................................................................................................3
Chapter2 hole machine standard and terminal functions...........................................................................................................3
2-1 Basic standard .............................................................................................................................................................3
2-2 Introduction of terminals(practicality photos).............................................................................................................4
Chapter3 Main chip functions and the introductions of power supply......................................................................................5
3-1 Main IC and functions of LS18...................................................................................................................................5
3-2 Pin function description of LS18 chip.........................................................................................................................7
3-2-1 MSD308PX recommended operating power conditons................................................................................... 7
3-2-2 Pin function of DTI1-E4I1VH tuner................................................................................................................ 7
3-2-3 EN25Q64-104HIP brief introduction:.............................................................................................................. 7
3-2-4 74HC4052 brief introduction:..........................................................................................................................7
3-2-5 SGM330 brief introduction:.............................................................................................................................8
3.3 Brief introduction of power supply..............................................................................................................................8
Chapter4 The chassis frame diagram, mainboard power supply systems, mainboard interface definition and the waveform
of key points..............................................................................................................................................................................9
4-1 The chassis frame diagram..........................................................................................................................................9
4-2 Power supply system...................................................................................................................................................9
4-2-1 The composition and distribution of the TV power supply..............................................................................9
4-2-2 Pin voltage of the voltage adjustor on the mainboard....................................................................................10
4-2-3 Interface definition......................................................................................................................................... 11
4-3 The waveform of key points......................................................................................................................................12
Chapter5 Software upgrade instructions..................................................................................................................................13
5-1 Software upgrade tooling---there are two kinds of using upgrade tooling................................................................13
5-2 Software upgrade introduction..................................................................................................................................13
Chapter6: Classical accident maintenance procedures and examples ..................................................................................... 18
6-1 The thinking of don’t boot......................................................................................................................................... 18
6-2 Common problems for your reference......................................................................................................................18
Chapter7 High voltage and high current wearing parts list..................................................................................................... 19
Chapter8 Factory mode parameter setting instructions and notes........................................................................................... 20
8-1 Enter into the factory mode....................................................................................................................................... 20
8-2 Setting method of factory menu................................................................................................................................21
Chapter9 Instructions of LS18 module Circuit Schematic Diagram.......................................................................................22
Appendix ：Circuit Schematic Diagram..............................................................................................................................25
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Chapter1 Safety and notes
1-1 Installation notes
(1) Please don't beat or rub, scratch the surface of the LCD screen heavily, don’t touch it with your hand
casually.
(2) When the screen is dirty, please clean it with absorbent cotton or cotton cloth slightly.
(3) Please clean it timely when water or other viscosity pollution fall, which may make the LCD face or
color change.
(4) Please don’t make the LCD screen shaked by strong external force.
1-2 Attention points of operation and using
(1) Please unplug the power cable before moving the LCD screen.
(2) Please don’t change the original setting of the mainboard’s, if not, the brightness and white balance etc.
may not meet the specification.
(3) The radiation of a long time using in the room temperature is larger than the low temperature.
(4) Please note that the long displaying image may remain at the top when shutdown the machine.
(5) Please avoid the impact from the mobile phone to protect your TV.
1-3 Storage notes
(1)When stored for a long time, please keep the temperature between 0℃to 40℃,don’t expose the TV to
the strong sunlight, the humidity should be less than 85％RH.
(2)Please don’t put your TV under high humidity and high temperature environment, for example, the
temperature: 60℃, and the humidity: 85%RH.
(3)Please don’t put your TV under low temperature environment, for example, the temperature lower than
-25℃.
1-4 Dismantling notes
(1)As LCD screen is easy to be damaged, while dismantle, please attention to protect.
(2)Please attention the position of each screw when dismantle, in case to beat the wrong position when
install, if not, it may lead to crack or slide of the face frame.
(3) If you need to dismantle the power board or the mainboard, please attention the position and direction
of each line, especially the direction of the screen line, in case of causing accident when install. Before
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dismantle, we can take some photos of the line route for the comparison of installing.
(4)After check and maintenance, please assure that there is no foreign body in the machine when install.
1-5 High-voltage warning
The high-voltage of the LCD screen is generated by the power supply step-up board, without attention to
exposure to the high voltage, one may meet a serious electricity shock.
Chapter2 hole machine standard and terminal functions
2-1 Basic standard
Item Standard
LCD Panel
visual area 32” inches（opposite angles）(BOE)
the parameters are for
reference only,the specific
should accord to the standard
of the screen practicality of
the batch orders
aspect ratio 16:9
resolving ratio 1366 x768
visual area H x V 697.68m m (H) ×392.25m m (V)
display colour 16.7 million
contrast 4000：1
brightness 450cd/m²
visual angle 178°(horizontal)/178° (vertical)
react time 8ms
backlight life 50000 hours
color temperature cold/hot
TV function sound system B/G、D/K、I、M
color system PAL / SECAM / NTSC
A
udio and video
signal input
AV AV x 2 Audio L/R x 1
S-Video S-Video x 1
aberration signal YPbPr x 2 support to1080P ，Audio L/R x 1,
HDMI HDMI x3support to1080P
PC input
plug and use
input frequency H: 31.5K -50KHz
V: 60Hz to 75Hz
recommend 1024x768(60HZ)
Video output Output CVBS signal Output TV and AV signal ,
Audio L/R x
1
Audio output Audio output L / R 10W inner speakers for each channel
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Power power supply AC100V~240V, 50/60Hz
power achievement <150W
requirement for environment
operation temperature
storage temperature
operation humidity
+ 0° ~ + 40° ，
- 20 ° ~ + 60°
10% ~ 85%
appearance size W x H x D
net weight no accessory Kg
2-2 Introduction of terminals(practicality photos)
YpbPr2 audio input
SCART1
SCART2
HDMI1 input
PC input
RF input
YpbPr1 input
PC audio input
YpbPr1 audio input
HDMI2 input
PCMCIA Card Slot
YpbPr2 input
Side AV inputinput
HDMI3 input
Keypad input IR inputBacklight on/off
Audio outputLvds output
Usb input
Power input
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ATTENTION:
1.HDMI and YPbPr support to 1080P；
2.The recommendation resolving ratio of PC is 1024X768；
3.Side AV input must use a small board.
Chapter3 Main chip functions and the introductions of power supply
3-1 Main IC and functions of LS18
No. Item no. Model Main function
1 U21 DTI1-E4I1VH(JUB2.891.170) Tuner output IF signal
2 U2 MSD308PX Video decoder, image processor,A/D and D/A conversion
3 U4 AT24C04BN-SH-T Store HDCP key
4 U52 AO4459 Power switch
5 U9，U15 W9751G6IB-25 DDR
6 U24 EN25Q64-104HIP Store program
7 U37，U38 LR1117/A-3.3 5V to 3.3V LDO
8 U39 LR1117/A-1.8 5V to 1.8V LDO
9 U36 LR1117/A-2.5 5V to 2.5V LDO
10 U51 AP1534SG13 5V to1.32V DC to DC
11 U18 AS7805DTR-E1 12V to 5V LDO
12 U17，U19
PT2328-X-TP$PI5V330AQ$
PI5V330AQX$SGM330A-YQS
$CS43V30
Video Switch
13 U11 STA335BW Audio amplifier
14 U20 SN74LV4052 Audio switch
15 U53 AO4803A USB power switch
16 U30 HDBF36A8Dc SAW filter
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U4:EEPROM
U2: MSD308PX
U9:DDR
U24:FLASH U52:AO4459
U39: LR1117/A-1.8
U37: LR1117/A-3.3
U20: SN74LV4052
U18:AS7805DTR-E1
U36: LR1117/A-2.5
U51:AP1534SG13
U11: STA335BW
U10: DTI1-E4I1VH
(JUB2.891.170)
U15:DDR
U38: LR1117/A-3.3
U53:AO4803A
U19: SGM330A-YQS
U17: SGM330A-YQS
U30: SAW
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3-2 Pin function description of LS18 chip
3-2-1 MSD308PX recommended operating power conditons
3-2-2 Pin function of DTI1-E4I1VH tuner
PIN
SYMBOL
Description
1
NC
Not connect
2
VCC2
+5V POWER
3
RF-AGC
RF-AGC monitor(Not connect)
4
SCL
I2C Serial Clock
5
SDA
I2C Serial DATA
6
VCC3
+5V POWER
7
TU
Tuning voltage monitor(Not connect)
8
AS
Address
9
IF-AGC
IF AGC Control Voltage
10
DIF1
High level IF output1
11
DIF2
High level IF output1
12
AIF
Analog IF output
3-2-3 EN25Q64-104HIP brief introduction:
Pin introduction:
Pin NO.
Pin Name
I/O
Function
1
CS#
I
Chip Select
2
DO
O
Serial Data Output
3
WP#
I
White Protect
4
Vss
Ground
5
DI
I/O
Serial Data Input
6
CLK
I
Serial Clock
7
NC
I
Not Connect
8
VCC
Power Supply
3-2-4 74HC4052 brief introduction:
Pin introduction:
Pin SYMBOL Function description
1,5,2,4 2Y0 to 2Y3 Independent Input Outputs
6 INH INHIBIT Input
7 VEE Negative Supply Voltage
10,9 A,B Select Inputs
12,14,15,11 1Y0 to 1Y3 Independent Input Outputs
3 2-COM Common X Output/Input
13 1-COM Common Y Output/Input
8 GND Ground
16 VCC Positive Supply Voltage
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3-2-5 SGM330 brief introduction:
Pin introduction:
Pin SYMBOL Function description
2,3,5,6,10,11,13,14 S1A, S1B, S1C, S1D
S2A, S2B, S2C, S2D Analog video I/O
1 IN Select input
15 EN Switch-enable input
4,7,9,12 DA, DB, DC, DD Analog video I/O
8 GND Ground
16 V+ Power supply
3.3 Brief introduction of power supply
AC input
AC100-240V
50/60HZ
U
se for LCD backlight
power supply.
12V
12V
GND
GND
5VSB
5V
24V
24V
24V
GND
U
se for mainbord power
supply.
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Chapter4 The chassis frame diagram, mainboard power supply systems,
mainboard interface definition and the waveform of key points
This chapter mainly introduce the chassis frame diagram, power supply system, interface definition and
each key point’s wave shape.
4-1 The chassis frame diagram
4-2 Power supply system
Power board has two kinds of output voltage: +12V and +5V.
4-2-1 The composition and distribution of the TV power supply
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4-2-2 Pin voltage of the voltage adjustor on the mainboard
item No. U39 U51 U37,U38 U36 U18
output voltage 1.8V 1.32V 3.3V 2.5V 5V
3.3V
2.5V
5V
PIN4,5 =5V
PIN9,10=12V
1.8V
1.32V
3.3V
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4-2-3 Interface definition
ON/OFF
GND
GND
5V
5V
5VSTB
GND
GND
12V
12V
Used for USB POWER
LED IRBacklight ON/OFF KEY
R-
R+
L-
L+
side AV’s signal
HDMI3’s signal
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4-3 The waveform of key points
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Chapter5 Software upgrade instructions
5-1 Software upgrade tooling---there are two kinds of using upgrade tooling
1.Use the combined interface(the parallel port) upgrade tooling: use the upgrade programme: TV
Utility_4.4.
2.Use interface upgrade tooling, use the upgrade programme: versions higher than TV Utility_4.4
5-2 Software upgrade introduction
1. Set up ISPTooling.
2.Open the ISPtooling and select “Connect”
Computer upgrade
tooling
LCD TV
Combine interface or USB
VGA
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3.Pls select “OK” once you connect the tooling successfully
4.Select “Read”
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5. Choose right SW document and open the file.
6. Select “Auto”
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7. Select “Run”.
8. The SW is updating.
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9. Pls turn on the TV again once the SW is updated successfully.
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Chapter6: Classical accident maintenance procedures and examples
6-1 The thinking of don’t boot
6-2 Common problems for your reference
To speed you to dignose and solve problems, the following commom problems are offered for your
reference
Symptoms Possible Reason Solutions
No picture, no sound, and no
indicator light on 1.The power cord is not plugged in
2.The power is off 1.Plug in the power cord 2.Turn the power on
abnormity Picture and sound with
1.Contrast, sharpness, and color are set
improperly
2.Color system is improperly
3.Sound system is improperly
1.Adjust the numberical value of
Contrast, sharpness, and color
2.Set the Color system to the country
broadcasting standard
3.Set the Sound system to meet the
country’s broadcasting standard
Picture is spotted or with snow Signal source is low-
grade or the signal
cord is in a lower quality Use the qualified signal cord
No picture, no sound and indicator
light is green
Contrast, brightness, color and volume are
all in the minimum value or TV is in mute
mode.
Adjust the value of contrast,
brightness, color and volume
The signal cable is not correctly connected.
Connect the signal cable correctly
Blue screen, AV or SVIDEO is
displayed
There is no signal input or the video cable is
not connected or incorrectly connected
Connect the video cable correctly
No sound
There is no audio signal input or audio
cable is not connected correctly
Connect the audio cable correctly
VGA picture display with improper
color
The color temp is adjusted incorrectly by
user
Readjust the color temp, or select
the original color setting
HDMI source, with snow pixel of
full screen
The signal source is not normal Plug the HDMI cable again
The remote control does not work
Batteries are improperly installed or
exhausted
1. Make sure the positive and the
negative polarities are correct.
2.Check if there is a loose contact
between the batteries and the springs
3.Replace the batteries
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Chapter7 High voltage and high current wearing parts list
The introduction of maintenance parts are for reference only, modification of parameters will not be
informed any more. For accurate data and related specifications, please consult the newest data of our
company.
Number Name Part number Print plate number
Proportion of easy
damage
（‰）
1 Side AV board part JUG6.693.241
Print plate
JUG7.820.621 1
2 Side usb board part JUG6.693.224 Printplate JUG7.820.513 1
3 Mainboard part JUG6.690.711
Print plate
JUG7.820.745-1 1
4 Remote receiving
board part JUG6.695.424
Print plate
JUG7.820.426 0.5
5 Keyboard part JUG6.694.469
Print plate
JUG7.820.554-1 0.5
6 Inner power module MLT868 Inner power module 5
7 LCD screen LTA320AP02 LCD screen 0.1
8 Dynamic speaker YDT415-A1-10W-8Ω Dynamic speaker 2
9 Remote control emitter GCBLTV10A Remote control emitter 1
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