Diamond View DV155 User manual

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DIAMOND VIEW
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Service Manual for Diamond View
TFT Monitors: DV155 & DV155B
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The release of this document is under control of the company. Extra copies
of this document must be by written permission of the product manager.
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Diamond View DV155 & DV155B
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Content
Chapter Page
A. WARNING 4
B. SAFETY PRECAUTIONS 5
1. DIMENSIONS 6
2. GENERAL INFORMATION 8
3. SPECIFICATIONS 9
4. THEORY OF OPERATION 14
5. DISASSEMBLY INSTRUCTIONS 17
6. CONTROL LOCATION 19
7. NECESSARY EQUIPMENT LIST 24
8. BLOCK DIAGRAM 25
9. CONDUCTOR VIEW 26
10. SCHEMATIC DIAGRAM 30
11. EXPLODED VIEW 35
12. TROUBLE SHOOTING HINTS 36
13. REPLACEMENT PARTS LIST 38
14. SPARE PARTS LIST 41
15. AUTO BALANCE 42
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WARNING
This service information is designed for experienced repair technicians only and is not
designed for use by the general public.
It does not contain warnings or cautions to advise non-technical individuals of
potential dangers in attempting to service this product.
Products powered by electricity should be serviced or repaired only by experienced
professional technicians.
Any attempt to service or repair the product or products dealt within this service
information by anyone else could result in serious injury or death.
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SAFETY PRECAUTIONS
1. CAUTION:
No modification of any circuit should be attempted. Service work should only be performed after you
are thoroughly familiar with all of the following safety checks and servicing guide lines.
2. SAFETY CHECK
Care should be taken while servicing this LCD display because of the high voltage used in the inverter circuit.
These voltagesare exposed in such areas as the associated transformer circuits.
3. POWER SUPPLY REQUIREMENTS
The external power converter for this display utilizes AC and DC cords, the AC cord is detachable,
but the DC cord is permanently attached. Any attempt to replace another adapter could result in serious
problem on the display.
4. LEAKAGE CURRENT HOT CHECK
4-1 Plug the AC cord directly into the AC outlet. Do not use an isolation transformer during this check.
4-2 Connect a 1500 ohm, 10 watt resistor, paralleled by a 0.15uF capacitor between each
metallic part and a good earth ground.
4-3 Use an AC voltmeter with 1000 ohm / volt or more sensitivity and measure the AC voltage
across the combination 1500 ohm resistor and 0.15uF capacitor.
4-4 Move the resistor connection to each exposed metallic part and measure the voltage.
4-5 Reverse the polarity of the AC plug in the AC outlet and repeat the above measurement.
4-6 Voltage measured must not exceed 1.5 volt RMS, from any exposed metallic part to the ground.
A leakage current tester may be used in the above hot check, in which case any circuit measured
must not exceed 1 milliamp. In the case of a measurement exceeding the 1 milliamp value,
a rework is required to eliminate the chance of a shock hazard.
To Metal Parts
V
AC VOLTMETER
1500 10W
0.15u
.
Earth Ground
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1. DIMENSIONS (Unit: mm)
1.1 Front View (ID1)
1.2 Top View
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1.3 Rear View
1.4 Side View
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2. GENERAL INFORMATION
2.1. OUTLINE
This monitor is 15" multi-scan color LCD display with the following features.
OSD (on screen display) control allows easy user adjustment.
Power saving function, which helps saving energy, is also one of the highlights of this model.
2.2. FEATURES
2.2.1 Power Saving
Built in Power Saving function based on VESA-DMPS standard. Power energy shall be saved
by controlling the circuit in accordance with power save signal from computer.
2.2.2 OSD (on screen display) function
OSD (5 Languages) function is excellent and new man-machine interface.
Anyone is able to set up the picture as they like through the OSD menu.
2.2.3 Self Test function
Self Testing picture comes out by pushing any key in the case of no-connection with computer
or power saving operation. This function shows if monitor is alive or not and can be used for self
aging test.
2.2.4 Ergonomic design
Low emission design to meet MPR II and TCO
2.2.5 Multi scan with digital technology
8 bit micro controller controls the circuit operation to meet with wide range signal of
Fh=31~61 kHz and Fv= 56~75 Hz. So VGA640x400, VGA640x480, SVGA800x60, XGA 1024x768,
2.2.6 Factory preset
The product has 21 memory modes in total. 12 modes are preset and 9 modes are user definable.
2.2.7 Fine dot pitch
LCD panel with a fine dot pitch (Horizontal: 0.297 mm / Vertical: 0.297 mm)
2.2.8 Superior display performance
High contrast: 400: 1(Typical)
High brightness: 250 cd / m2 (Typical)
Wide view angle: 120 / 90 degrees (H/V)
2.2.9 Special function
VESA DDC2B (Display Data Channel) Compatible
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3. SPECIFICATION
3.1. Outline
3.1.1 Front Indication: POWER SW, LED (Green/Amber), UP, Down, LEFT, RIGHT, Set/Auto and MENU
key are located on the front panel.
3.1.2 Video signal cable connector, audio line-in receptacle and DC inlet are located on the back side cabinet.
3.1.3 OSD menu includes the following function. CONTRAST, BRIGHTNESS, H.POSITION, V.POSITION
COLOR-TEMPERATURE, CLOCK, PHASE, LANGUAGE, VOLUME, POWER-ON-RECALL
3.1.4 CONTRAST and BRIGHTNESS can be directly controlled with UP / Down key.
3.1.5 VOLUME can be controlled with LEFT / RIGHT key.
3.2. MECHANICAL SPECIFICATIONS
3.2.1 Dimension Height: 371 mm (14.7")
Width: 348 mm (13.7")
Depth: 157 mm (7.2")
3.2.2 Net Weight: 5.6 kg (12.4 lbs)
3.2.3 Maximum Viewable Area: Diagonal 381mm (15")
3.3. PANEL SPECIFICATIONS
Part No.
x=0.312,y=0.318 Color coordinate white
60/60/55/45 degrees View angle (L/R/T/B)
Typical 25 ms Response time
0.297 mm Pixel pitch
250 cd / m2 Brightness
400:1 Contrast ratio
6 bit Driver bit of panel
CLAA150XG08
3.4. CONNECTORS
3.4.1 AC inlet: CEE22 typed connector
3.4.2 Audio: Line-in receptacle
J1
PHONEJACK STEREO
1
2
3
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3.4.3 Attached video signal cable connector x 1
Figure 3.4
Si
g
nal cable in
p
ut connector.
Shell
1 2 3 4 5
10
12
11
6
13 14 15
Pi
n
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Si
g
nal Name
Blue video
Green video
Red video
Vs
y
nc
(
VCLK
)
Ground
Hs
y
nc
Ground
N
/C
Blue return
Green return
Red
g
round
Ground
Groun
d
SDA
(
serial data
)
SCL
(
serial clock
)
3.5. ELECTRICAL SPECIFICATIONS
3.5.1 Standard conditions
Display area (HxV)
1024 x 768 Display mode
More than 30 minutes Warming up time
AC 220,50Hz Input voltage
25 +/- 5 C degrees Ambient Temperature
Max. Brightness
Max. Contrast
0.7 Vpp Video signal level
304 x 228 mm
3.5.2 POWER
3.5.2.1 Power supply
AC-DC adapter
Input voltage 90 - 264 V
Input current max. 1 Arms
Output voltage 12VDC, 350mA, 3.3V 2A
Frequency range 47 - 63 Hz
Inrush current Shall be less than the ratings of critical components
(including fuse, rectifiers and surge limiting device)
for all conditions of line in voltage.
Maximum power consumption: 35 Watts
3.5.2.2 Power Management
The Power Management System complies to TCO 99 standards < 3 W.
MODE H-SYNC V-SYNC COLOR OF
POWER LED
POWER CONSUMPTION RECOVERY TIME
On Active Active Green < 35 Watts -
Off Inactive Inactive Amber < 1 Watts < 30 seconds
Remark: In case of “no signal“ Power LED must be amber.
At first power on w/o signal LED will be green + message on screen.
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3.5.3 Signal level and input impedance
3.5.3.1 Video Signal level
This LCD display is adjusted at the factory using 0,7 Vp-p Video signal.
3.5.3.2 Sync Signal level
H/V Separate: TTL level
3.5.3.3 Input impedance
Video input: 75 ohms
Sync input: > 1 k ohms
3.5.4 Display Area
Display area: 304 x 228 mm
3.5.5 Preset Timings
The product has 21 memory modes in total. 12 modes are preset and 9 modes are user definable.
T
iming 1 2 3 4 5 6 7 8 9 10 11 12
Standard DOS VESA VESA VESA VESA VESA VESA VESA VESA VESA Industry VESA
Data Pixel 640 640 640 640 720 800 800 800 800 1024 1024 1024
Data Line 350 480 480 480 400 600 600 600 600 768 768 768
H-Freq
kHz 31.469 31.469 37.861 37.500 31.467 35.156 37.879 48.077 46.875 48.363 56.180 60.023
V-Freq Hz 70.087 59.942 72.809 75.000 70.082 56.250 60.317 72.188 75.000 60.004 69.960 75.029
Pix Rate
MHZ 25.175 25.175 31.500 31.500 28.320 36.000 40.000 50.000 49.500 65.000 74.160 78.750
Hor.A [us] 0.318 0.636* 0.508 0.508 0.616 0.667 1.000 1.120 0.323 0.369 0.323 0.203
Hor.B [us] 3.813 3.813 1.270 2.032 3.813 2.000 3.200 2.400 1.616 2.092 2.373 1.219
Hor.C [us] 1.907 1.907* 3.810 3.810 1.907 3.556 2.200 1.280 3.232 2.462 1.294 2.235
Hor.D [us] 25.422 25.422 20.317 20.317 25.442 22.222 20.000 16.000 16.162 15.754 13.810 13.003
Hor.E [us] 31.778 31.778 26.413 26.667 31.778 28.444 26.400 20.800 21.333 20.677 17.800 16.660
Vert.A
[ms] 0.191 0.381 0.026 0.027 0.382 0.028 0.026 0.770 0.021 0.062 0.018 0.017
Vert.B
[ms] 0.064 0.064 0.079 0.080 0.064 0.057 0.106 0.125 0.064 0.124 0.142 0.050
Vert.C
[ms] 1.907 1.048# 0.528 0.427 1.111 0.626 0.026 0.478 0.448 0.600 0.463 0.466
Vert.D
[ms] 11.122 15.253 12.678 12.800 12.711 17.067 15.840 12.480 12.800 15.880 13.670 12.795
Vert.E
[ms] 14.268 16.683 13.735 13.333 14.268 17.778 16.579 13.853 13.333 16.666 14.293 13.328
Sync.Pol. +/- - / - - / - - / - -/+ + / + + / + + / + + / + - /- + / + + / +
Note: *Indicates horizontal front / back porch includes borders
# Indicates vertical front / back porch includes borders
3.5.6 General performance
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3.5.6.1 Maximum pixel clock
78.85 MHz
3.5.6.2 Maximum luminance
Test conditions: 100% all white pattern, brightness set to Maximum
typical: 250 cd/m2
min: 200cd/m2
3.5.6.3 Brightness variation
Value
Display image: Full white
Brightness: Maximum
Contrast: Maximum
A: Luminance at center position
C: Luminance at position of lowest
brightness
Conditions
75 % Variation (C / A x 100)
3.5.6.4 Contrast ratio (CR)
Value
Contrast: Maximum
Brightness: max
B: Full white pattern
A: Full black pattern
Conditions
CR= B / A
3.6. ENVIRONMENTS
The environmental conditions are in accordance to IEC 721
Operating:
Temperature: 5°C - +40°C
Humidity: 20% - 80%
Height: 3000 m
Air pressure:
700 - 1060 mbar
Storage (unpacked)
Temperature: -20°C - +60°C
Humidity: 10% - 85%
Height: 3000 m
Air pressure: 700 - 1060 mbar
Transport (packed)
Temperature: -30°C - +60°C
Humidity: 5% - 95%
Height: 12000 m
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3.7. REGULATORY STANDARDS
3.7.1 Safety standards
This monitor applies to various safety & EMI standards refer to the logo label
3.7.2 EMC standards
C Tick, AS/NZS CISPR 22:2002, CE marking
3.8. OTHERS
CB report for AS/NZS 60950:2000 (based on IEC 60950:1999)
3.9. P0WER CORD
Australia power cord
3.10. SIGNAL CABLE
Signal cable with Mini D-Sub 15P connectors, Length: 1.8 meter.
3.11. RELIABILITY
MTBF > 30000hrs (demonstrated MTBF)
For LCD panel:
The brightness is still more than 50% of the original brightness after:
typ. 20.000 hours
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4. THEORY OF OPERATION
This section describes the function of the LCD monitor per functional block.
L5EP monitor includes MB board (including audio board function inside), inverter board, adapter and button board.
4.1 MB BOARD
The MB board is a four-layer, single-landed design with ground and internal planes provided. DC power
from the power adapter enter the board through DC jack. Other connectors on the board are for inverter,
and button board .The VGA cable is a signal cable that contains video signal, sync signal and DDC
signal from PC VGA adapter.
The system board consists of 3 functional areas: flat panel controller, micro-controller, power regulator
4.1.1 Flat panel controller…… MST8016 (U2)
The heart of the system board is MST8016. The MST8016 is a graphics processing IC for LCD monitor.
It provides all key IC functions required for LCD panel. On-chip functions include a high-speed
triple-ADC, PLL, high scaling engine, and OSD controller.
a) Clock Generation:
Crystal Input Clock (TCLK and XTAL). This is the input pair to an internal crystal oscillator and
corresponding logic. A 14.318 MHz crystal is recommended.
b) Hardware Reset ( Pin 155 )
Hardware Reset signal is generated by micro-controller (U4, pin 36). It assert a reset signal at least 100 ms.
c) Analog to Digital Converter
The MST8016 chip has three ADC's (analog-to-digital converters), one for each color (red, green and blue)
The analog RGB signals are connected to MST8016 as described below
Pin Name
48 Blue -
47 Blue +
54 Green -
53 Green +
60 Red -
59 Red +
Pin Number
d) Panel Power Sequencing (VDDCTRL, INVCTRL) ( Pin20~21)
The MCU has two dedicated outputs VDDCTRL1, 2 and INV CTRL (Pin9, 16 and Pin36) to control LCD power
sequencing once data and control signals are stable.
e) Panel interface (Pin 66~137)
The MST8016 driver interface is highly programmable. It supports dual bus / dual port for XGA drivers.
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4.1.2 Microcontroller MT312 (U4)
The MT312 is a microcontroller serves as the system microcontroller. That is, it programs the
MST8016 and manages other devices in the system such as the keypad, the backlight, LED, audio and
non-volatile RAM. using general purpose input/output (I/O) pins.
Pin No
Provide Reset signal for MST8016 P1.4 (Reset) 22
EDID clock connect to VGA port P3.5 (VGA SCL) 29
EDID data connect to VGA port P3.1 (VGA SDA) 28
Control button input P6.0 (KEY in) 27
For VGA signal check P1.7 (DSUB_5V) 25
Control LED red P5.3 (LED Red) 42
Control LED green P5.4 (LED Green) 41
Control audio volume to mute P4.1 (MUTE) 37
For inverter on/off control P4.0 (INVCTRL) 36
For Panel power control
P6.3, P6.29, 16
Connect to MST8016
P3.2 (INT) 19
For On/Off power button
P6.1 (PWR KEY) 26
Clock signal for serial communication P1.3 (SCL) 21
Data signal for serial communication P1.2 (SDA) 20
Pin Usage Pin Name
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4.1.3 Power reference AIC1739 (Q3)
The AIC1739 is a 2.5V voltage provider. It could support maximum 100mA current capability. The 2.5V reference was for
scaler MST8016 reference. The voltage was very important for this all the function that MVZ have.
4.2 Inverter/Power/Audio Board
This is a specific inverter/Power/Audio module for L5TD monitor with backlight/EE parts/audio function.
4.2.1 Inverter function
The inverter converters 12 Vdc to drive two cold cathode fluorescence tubes. Electrical specification described as below.
INPUT
7.5 mA Rate Output Current per tube
50~60KHz Rated Output Frequency
675 Vrms at 7.5 mA Rated Output Voltage
1100 Vrms Rated Output Strike-on Voltage
OUTPUT
20~98 % duty cycle On / Off Voltage
< 0.1 W Off state Input Power
<1. 2A Input Current
11.4~12.6 Vdc Maximum Input Voltage
12Vdc (L5EP) Rated Input Voltage
4.2.2 Adapter
This is a general purpose AC / DC adapter which converter 90~240 Vac to a stabilized DC voltage 12 V
with rated output current of 3A . Electrical specification described as below
INPUT
< 1 Second Turn-on Delay
< 250mA and 2.0A Rate Output Current
< 120 and 100 mVp-p Output Ripple and Noise
+ 5 / -5 % and Output Voltage Regulation
12 Vdc and 3.3Vdc Rated Output Voltage
OUTPUT
< 1.0 W (3.3V 30mA) Standby Input Power
< 50A @ all input range Inrush Current (Cold Start)
< 1.0A Input Current
90~264 Vac, 47~63 Hz Operation Input Voltage
100~240 Vac , 50/60 Hz Rated Input Voltage
4.2.3 Audio amplifier TDA7496
The TDA7496 on the power board is a 2 channel audio power amplifier capable of delivering 1W of continuous average power
to an 8 ohms with less than 10% (THD) from a 12 V power supply.
TDA7496 can directly drive 8 ohms speaker, does not require output coupling capacitor, bootstrap capacitor, or snubber
network. Audio line-in are fed into pin 4,8 of the AN7522. The output power is controlled by
the DC voltage of pin 39 from MTV312 I / O port.
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5. DISASSEMBLY INSTRUCTIONS
1.Stand and & rear cover removal
1) remove four large screw "1" from
the rear cover
2) remove the back cover
2. Bezel removal
1) remove screw "1" & “2” from
the Bezel
2) remove the bezel
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3. Inverter cover & Inverter board removal
1) remove two screws "1", “2” & “3”
2) remove the shield cover
3) remove two screw "4"
4) remove cable 4 & 5 then remove
Power/Inv board
4. AD board removal
1) remove cables 1, 4 & 5
2) remove screw “2” & “3”
3) remove the AD board
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6. CONTROL LOCATION
Button Define
1 MENU OSD Menu Trigger OSD Main Menu / Clear OSD
2
UP
1. Select OSD Main Menu Item
2. Trigger Brightness/Contrast Menu.
3
DOWN
1. Select OSD Main Menu Item
2. Trigger Brightness/Contrast Menu.
4 LEFT
1. Decrease Menu Item value
2. Trigger Volume Menu.
5 RIGHT
1. Increase Menu Item value
2. Trigger Volume Menu.
6 SELECT/AUTO SELECT/ AUTO 1. Switch OSD Main Menu focus status.
2. Perform Auto configuration.
7 POWER POWER Switch Power ON/OFF
Color Status Description
Green Normal status
Amber
Enter Sleep Mode status or use “Power + Auto” k e
y
enter
factory mode
LED Status
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Dialog Overview
 OSD Main Menu
 Brightness/Contrast Menu
When user press the Menu ke
y
under none
OSD status will trigger this menu
a
pp
ear for detail
p
arameters adjust.
This menu will dis
p
la
y
about 45 seconds
if no one
p
ress other ke
y,
otherwise
will refresh display time length.
When user press the Up or Down keys
under none OSD status will tri
gg
er this
menu appear for Brightness and
Contrast adjust. This menu will
display about 45 seconds.
 Volume Menu
When user press the Left or Right
keys under none OSD status will
tri
gg
er this menu a
pp
ear for Volume
adjust. Use the Left & Right ke
y
s
adjust the volume value
,
and use the
Up & Down keys switch the Mute
status. This menu will dis
p
la
y
about
45 seconds.
 Auto Configuration
When user press the select/Auto ke
y
under none OSD status will tri
gg
er
this dialo
g
a
pp
ear and
p
erform Auto
Configuration procedure.
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 Mode Information
When Display timing changed this
dialo
g
will a
pp
ear about 5 seconds.
And this feature only enable when
“Information” indicate On in OSD’s
other page of main menu.
 No Signal
W
hen user in
p
ut not su
pp
orts the video
si
g
nal from the cable this dialo
g
will
appear about 20 seconds. And then
enter the Slee
p
mode. One s
p
ecial case
w
as in factor
y
mode
,
the dis
p
la
y
time
length will become 5 seconds for
testing the power consumer.
 Out Of Range
W
hen user in
p
ut the video si
g
nal out
of s
p
ec this dialo
g
will a
pp
ear about
20 seconds. And then enter the Slee
p
mode.
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