Technical description and composition of the DAEWOO L28S620VBE TV, type of panel and applicable modules. The composition of the modules.DAEWOO LED
Model: L28S620VBE
Chassis / Version: TP.MS3463S.PB751
Panel: BOEI280WX1 // HV280WX2-270
LED backlight: GC275D06-ZC14F-03 303GC275031 (HV280 ..)
LED driver (backlight): integrated into MainBoard
MOSFET LED driver: D4454
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MainBoard: TP.MS3463S.PB751
IC MainBoard: SPI Flash: GD25Q64CSIG
Tuner: XF-3SDT-H
Technical Specifications L28S620VBE
DAEWOO L28S620VBE
General repair guidelines for TV LCD LED
Possible manifestations of defects
- The DAEWOO L28S620VBE TV does not turn on and does not show any signs of turning on, it does not respond to the control buttons or the remote control.
In such cases, the common power source, the AC / DC voltage converter, which is combined with the elements of the main board TP.MS3463S.PB751, often turns out to be faulty. Then we recommend that you measure its output voltages and, if they are absent, you should check the health of the power switches and rectifier diodes of the converters for a probable short circuit.
In case of any breakdowns in the secondary circuits, the converter can operate in emergency short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse or the current sensor at the source of the key more often breaks.
Breakdown of power switches (MosFet) in pulsed sources is sometimes caused by malfunctions of other circuit elements, for example, in circuits supplying a PWM controller, frequency-setting or damper ones, as well as in negative feedback circuits (OOS) of stabilization. PWM controllers (PWM) PWM SOT23-6, if they do not have visible damage to the case and open short circuit between the terminals, are usually checked by replacement.
- There is no image, there is sound, all other functions of the TV work. When turned on, the image may sometimes appear for a second.
Often in such cases, there is no LED backlight. Often the cause is a malfunction of the LEDs (open circuit, short circuit ...), or the connectors of the strips (strings), less often the LED driver is malfunctioning.
It is impossible to detect a break in the LED line without disassembling the panel with a simple multimeter. The LEDs are connected in series and to open their transitions, a voltage of several tens of volts is required. Ideally, a current source is suitable for such purposes. You can open the panel and check each LED separately. Typically, Chinese multimeters light up a single 3-volt LED, if you connect the probes in the forward direction to it (red probe to the anode, black to the cathode). In dual 6-volt LEDs, the PN junction of its emergency zener diode can serve as an indicator of health. In the event of a LED malfunction, its zener diode will either be cut off or broken into short-circuit.
- The TV does not turn on, the indicator indicates standby or operating mode, or blinks.
Repair or diagnostics of the TP.MS3463S.PB751 motherboard should begin by checking the stabilizers and power converters needed to power the chips and matrix. If necessary, update or replace the software (software). In some cases, to repair the MB board (SSB), it may be necessary to replace the chips - SPI Flash: GD25Q64CSIG with new or obviously good ones. In cases where BGA technologies are used, defects are usually localized by the heating method.
If the TV works normally from external devices, but does not tune into television channels, the tuner XF-3SDT-H may be malfunctioning. In such cases, first of all, you should make sure that there are supply voltages at its corresponding conclusions. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus. Sometimes the cause of the inoperability of the tuner may be a software failure.
Once again, remind users! Attempts to self-repair a TV DAEWOO L28S620VBE without the appropriate qualifications and the necessary experience can lead to its complete non-repairability!
FIRMWARE FOR SPI FLASH -----------> DAEWOO L28S620VBE, Main: TP.MS3463S.PB751, Panel: BOEI280WX1
The appearance of MainBoard TP.MS3463S.PB751 is shown in the figure below:TP.MS3463S.PB751
Main features of the device DAEWOO L28S620VBE:
Installed matrix (LED-panel) BOEI280WX1 or HV280WX2-270.
To power the backlight LEDs, a converter is used, combined with the main board TP.MS3463S.PB751. As the power elements of the LED driver, keys of the D4454 type are used.
The power module is combined with the MainBoard and is made according to the flyback AC / DC voltage converter circuit using PWM SOT23-6 microcircuits.
MainBoard - the main board (motherboard) is a TP.MS3463S.PB751 module, using SPI Flash chips: GD25Q64CSIG and others.
The XF-3SDT-H tuner allows you to receive television programs and tune to channels.
Brand: DAEWOO, Model: L28S620VBE.
Briefly from the TV: LCD, LED backlight, 28 ", 1366x768, 720p HD, DVR, sound: 12 W, HDMI connectors: 2.
The composition uses MainBoard TP.MS3463S.PB751 and the LCD panel (matrix) BOEI280WX1. The power supply is combined with the MainBoard.
Technical description
DAEWOO L28S620VBE LED TV with a BOEI280WX1 LCD display, diagonal size 28 "(71 cm) in 16: 9 format. The required screen brightness of 200 cd / m² is provided by LED backlight LED. The LED display backlight is implemented in the model display technology. Viewing is possible images in high quality HD at a resolution of 1366x768 pixels in the standard of graphic decomposition 720p (HD Ready) Supported media file formats: MP3, MPEG4, JPEG.
The power of the sound system 12 W (2x6 W) provides two speakers. The audio processing system NICAM STEREO is used.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, component, VGA, HDMI x2, USB. An output for connecting headphones is provided. A digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-T2 standards.
The power consumed by the TV in the operating mode from the network is 60 watts.
Overall dimensions: with stand 639x416x185 mm, without stand 639x385x76 mm.
Mass of the TV: 4.1 kg.
Attention! The BOEI280WX1 panel of a DAEWOO L28S620VBE LED TV is an expensive and unreliable element.
Avoid any impact on the glass and pressure on the surface of the screen to avoid damage to the LED panel!
It is also unsafe to get liquid on the screen. Sometimes one drop is enough if it flows down the glass onto the cables so that the TV becomes unrepairable.
