Technical description and composition of the BBK 50LEX-5026 TV, type of panel and applicable modules. The composition of the modules.BBK LED
Model: 50LEX-5026 / FT2C
Chassis / Version: CV338H-T50
Panel: CX500DLEDM LE-5019
LED backlight: 30805HL050660Z03 HL-00500A30-0901S-04
LED driver (backlight): integrated into MainBoard
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MainBoard: CV338H-T50
IC MainBoard: CPU: MSD6A338SXG-0071, Nand: KLM4G1FEPD, Audio: MP7752
Tuner: NoName
Technical Specifications 50LEX-5026 / FT2C
BBK 50LEX-5026
General repair guidelines for TV LCD LED
Possible malfunctions
- BBK 50LEX-5026 does not turn on, the indicators on the front panel do not light or flash. The TV does not respond to the control buttons and the remote control.
In this case, the main power source - the AC / DC network voltage converter, the elements of which in this model are located on the MainBoard CV338H-T50 general board, may turn out to be faulty. It is necessary to measure its output voltages, and in case of their absence (full or partial), it is necessary to check the serviceability of the power switches of the converters and rectifier diodes for the presence of a possible 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.
Mos-Fet power switches, used in switching power supplies, sometimes fail due to a malfunction of any other elements that can put it out of operation in key mode or create an excess of the maximum permissible parameters of the switch. These can be elements supplying the PWM controller, frequency-setting or damping circuits, or negative feedback elements in the stabilization circuit. PWM SOT23-6 PWM controllers, in the absence of visible damage or obvious short-circuit between the terminals, are checked by replacing with new ones, or obviously working.
- There is no image, there is sound, it responds to the remote. Or the image may appear for a second when turned on and immediately disappears.
In most of these cases, a malfunction is detected in the nodes and backlight elements of the LED panel. Often the cause of the malfunction is the lack of current in the LED circuit, for example, an open or short circuit, or a violation of the contact connections of the connectors.
To check the LED strips, to open all the transitions of the LEDs, several tens of volts or more are needed, it is best to use a current source for such purposes. The breakage of several PN junctions connected in series cannot be detected with a multimeter or tester. In such cases, it is necessary to open the panel and check each LED. If your multimeter cannot open the LED transitions in forward bias, sometimes you can detect the presence of a PN junction of the protective zener diode by connecting the probes in the opposite direction. If the zener diode is broken or broken in short-circuit, then the LED is faulty and needs to be replaced.
- The indicator on the front panel blinks, the TV does not turn on in the operating mode, it does not respond to the remote control.
Repair or diagnostics of the CV338H-T50 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 cases of attempts to repair the MB board (SSB), it is necessary to check the health of its elements - CPU: MSD6A338SXG-0071, Nand: KLM4G1FEPD, Audio: MP7752 which may require replacement with new ones. If a BGA processor is installed, there is a possibility of a violation of the soldering of the contacts of its conclusions with the board (it is diagnosed by heating).
In cases where there is no tuning to the channels of on-air or cable television, you should make sure that the software is correct, as well as in accordance with the ratings of the supply voltage at the terminals of the NoName tuner. It is also necessary to check the presence of pulses of data exchange between the tuner and the processor via the I2C bus using an oscilloscope.
It should be remembered! Attempts to independently repair the BBK 50LEX-5026 TV, in the absence of the necessary qualifications and experience, are categorically not recommended and are fraught with negative consequences, up to the complete non-repairability of the device!
The appearance of the MainBoard CV338H-T50 is shown in the figure below:CV338H-T50
Main features of the BBK 50LEX-5026 device:
Installed matrix (LED-panel) CX500DLEDM LE-5019.
To power the backlight LEDs, a converter is used, combined with the main board CV338H-T50.
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 CV338H-T50 module, using CPU chips: MSD6A338SXG-0071, Nand: KLM4G1FEPD, Audio: MP7752 and others.
The NoName tuner provides television reception and channel tuning.
Brand: BBK, Model: 50LEX-5026 / FT2C.
Briefly from the TV: LCD, 1080p Full HD, diagonal 50 "(127 cm), Smart TV (Android), Wi-Fi, HDMI: 2, USB: 3, there is support for DVB-T2.
The composition uses MainBoard CV338H-T50 and LCD-panel CX500DLEDM LE-5019. The power supply is combined with the MainBoard.
BBK 50LEX-5026 / FT2C LED TV with CX500DLEDM LCD, 50 "(127 cm) diagonal size of 16: 9 format. The required screen brightness of 250 cd / m² is provided by LED backlighting. The ratio of maximum brightness to minimum (contrast) is 5000: 1. The LED display is implemented in the manufacturing technology of the model’s display.The design and technical capabilities of the TV include watching programs and movies in high quality HD at a resolution of 1920x1080 pixels in a graphical decomposition according to the standard 1080p (Full HD).
50LEX-5026 / FT2C has built-in SMART Software and pre-installed Android Operating System. Connecting to the Internet can be done via Wi-Fi. Supported media file formats: MP3, WMA, MPEG4, MKV, JPEG. Stereo sound is realized by two built-in 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 x3, Ethernet (RJ-45), Wi-Fi 802.11n, Miracast. An output for connecting headphones is provided. The digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-C MPEG4, DVB-T2 standards.
Overall dimensions: With a support 1134x704x250 mm, Without a support 1134x662x92 mm.
Mass of the TV: 12.8 kg.
Attention! The CX500DLEDM LE-5019 panel of the BBK 50LEX-5026 / FT2C 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.
