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 a 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.
No modification of any circuit should be attempted. Service work should only be performed after you
are through 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 voltage are exposed in such areas as the associated transformer circuits.
3. POWER SUPPLY REQUIREMENTS
The internal power converter for this display utilizes a AC cord, the AC cord is detachable.
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.
This monitor is a 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
The Built in Power Save 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 he like through 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 TCO 99.
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, SVGA800x600, XGA 1024x768 are
possible.
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 : 350:1 ( Typical )
High brightness : 250 cd / m² ( Typical )
Wide view angle : 130 / 110 degrees ( H/V Typical )
Input voltage 100 - 240 V
Input current max. 1 Arms
Output voltage 12VDC, 350mA, 3.3V 2A
Frequency range 50 - 60 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: 40 Watts
3.5.2.2 Power Management
The Power Management System complies with TCO 99 standards.
MODE H-SYNC V-SYNC COLOR OF
POWER LED
On Active Active Green < 40 Watts -
Off Inactive Inactive Amber < 1 Watts < 30 seconds
POWER CONSUMPTION RECOVERY TIME
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.
This section describes the function of the LCD monitor per functional block.
Belinea 101555 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 3 functional areas: flat panel controller, micro-controller and power regulator.
4.1.1 Flat panel controller…… gmZAN2 (U1)
The heart of the system board is MRT MVZ. The MVZ 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 20 MHz crystal is recommended.
b) Hardware Reset ( Pin 155 )
Hardware Reset signal is generated by micro-controller (U1, pin 36). It assert a reset signal at least 100 ms.
c) Analog to Digital Converter
The MVZ chip has three ADC's (analog-to-digital converters), one for each color (red, green and blue)
The analog RGB signals are connected to MVZ as described below
Pin Name
Pin Number
59Red +
60Red -
53Green +
54Green -
47Blue +
48Blue -
d) Panel Power Sequencing ( VDDCTRL, INVCTRL) ( Pin20~21)
The MCU has two dedicated outputs VDDCTRL and INVCTRL ( Pin76 and Pin75) to control LCD power
sequencing once data and control signals are stable.
e) Panel interface (Pin 66~137)
The MVZ driver interface is highly programmable. It supports dual bus / dual port for XGA drivers.
The MT312 is a microcontroller serves as the system microcontroller. That is, it programs the
MVZ 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
Pin UsagePin Name
Data signal for serial communicationP3.4 (SDA) 13
Clock signal for serial communicationP3.5 (SCL) 14
The TL431 is a 2.5V voltage provider. It could support maximum 100mA current capability. The 2.5V reference was for scaler
MRT MVZ 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 L5TL 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
12Vdc (L5EP)Rated Input Voltage
11.4~12.6 VdcMaximum Input Voltage
<1. 2AInput Current
OUTPUT
< 0.1 WOff state Input Power
20~98 % duty cycleOn / Off Voltage
1100 Vrms Rated Output Strike-on Voltage
675 Vrms at 7.5 mARated Output Voltage
50~60KHzRated Output Frequency
7.5 mARate Output Current per tube
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
100~240 Vac , 50/60 Hz Rated Input Voltage
90~264 Vac, 47~63 Hz Operation Input Voltage
< 1.0AInput Current
< 50A @ all input range Inrush Current (Cold Start)
OUTPUT
< 1.0 W (3.3V 30mA) Standby Input Power
12 Vdc and 3.3VdcRated Output Voltage
+ 5 / -5 % and Output Voltage Regulation
< 120 and 100 mVp-p Output Ripple and Noise
< 250mA and 2.0ARate Output Current
< 1 SecondTurn-on Delay
4.2.3 Audio amplifier TDA7496
The AN7522 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 feed into pin 4,8 of the AN7522. The output power is controlled by
the DC voltage of pin 39 from MTV312 I / O port.