Technical description and composition of the BBK 42LEX-5026 TV, type of panel and applicable modules. The composition of the modules.BBK LED
Model: 42LEX-5026 / FT2C
Chassis / Version: CV338H-T42
Panel: V420HJ2-P01
LED driver (backlight): integrated into MainBoard
PWM LED driver: BIT3267
MOSFET LED driver: AOD4454
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MainBoard: CV338H-T42
IC MainBoard: MSD6A338, MSB102KT, W25Q16DVSSIG, MP7752
Tuner: CDT-9NT372RF-10 (R842)
Specifications 42LEX-5026 / FT2C
BBK 42LEX-5026
General repair guidelines for TV LCD LED
Possible malfunctions
- The BBK 42LEX-5026 TV does not turn on at all. There is no reaction to the remote control and control buttons from the front panel. Indicator lights do not light or flash.
The malfunction in such cases, first of all, should be sought in the power elements of a switching power supply (IIP) - a network voltage converter (AC / DC), which in this TV model is combined with the MainBoard CV338H-T42 main board. It is then necessary to measure its output voltages and, if they are absent, it is necessary to check the power switches and rectifier diodes of the converters for a short-circuit probability.
In case of breakdowns of semiconductors in the secondary circuits of any converter, as a rule, it can operate in emergency short-circuit mode without output voltages, and during short circuit in the elements of the primary circuit, the main fuse and, less often, the current sensor at the source of the key most often breaks.
The breakdown of power switches (MosFet) in pulsed sources is sometimes caused by malfunctions of other circuit elements, for example, in the circuits supplying the PWM controller, frequency-setting or damper ones, as well as in the circuits of Negative Feedback (OOS) 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, but there is sound, it reacts to the remote control. Or the image appears when you turn it on and immediately disappears
In such cases, the most likely malfunction of the LED backlight elements. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
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, does not respond to the remote control. The indicator blinks or signals standby mode.
Repair or diagnostics of the CV338H-T42 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). If it is not possible to replace the MB board (SSB), you need to check the health of its elements - MSD6A338, MSB102KT, W25Q16DVSSIG, MP7752. Defective components should be replaced.
If the TV works normally from external devices, but does not tune into television channels, the tuner CDT-9NT372RF-10 (R842) 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.
Attention TV owners! Attempts at self-repair of BBK 42LEX-5026 are not recommended by the manufacturer and can lead to serious negative consequences!
SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> BBK 32LEX-5024 Chassis CV338H-T42-13B
The appearance of the MainBoard CV338H-T42 is shown in the figure below:CV338H-T42
CV338H-T42 can be used in TVs:
BBK 32LEX-5023/T2C (Panel V320BJ6-Q01 Rev.C1 (TH32YS1705C0327)), BBK 32LEX-5024/T2C (Panel TH32YS1704D0089).
Main features of the BBK 42LEX-5026 device:
Installed matrix (LED panel) V420HJ2-P01.
To power the backlight LEDs, a converter is used, combined with the main board CV338H-T42, controlled by a BIT3267 PWM controller. As power elements of the LED driver, keys of the AOD4454 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 CV338H-T42 module, using microchips MSD6A338, MSB102KT, W25Q16DVSSIG, MP7752 and others.
The tuner CDT-9NT372RF-10 (R842) provides the reception of television programs and tuning to channels.
Additional technical information about the panel:
Brand: CHIMEI INNOLUX
Model: V420HJ2-P01
Type: a-Si TFT-LCD, CELL
Diagonal size: 42 inch
Resolution: 1920x1080, FHD
Display Mode: Super MVA, Normally Black, Transmissive
Active Area: 919.296x517.104 mm
Surface: Antiglare (Haze 1%)
Glass Depth: 0.50 + 0.50 mm
Transmissivity: 5.9% (with Polarizer)
Contrast Ratio: 4000: 1
Display Colors: 16.7M (8-bit)
Response Time: 9.5 (G to G)
Frequency: 60Hz
Signal Interface: LVDS (2 ch, 8-bit), 51 pins
Voltage: 12.0V
Brand: BBK, Model: 42LEX-5026 / FT2C.
Briefly from the TV: LCD, 1080p Full HD, diagonal 42 "(107 cm), Smart TV (Android), Wi-Fi, HDMI: 2, USB: 3, there is support for DVB-T2.
The composition uses MainBoard CV338H-T42 and LCD-panel V420HJ2-P01. The power supply is combined with the MainBoard.
BBK 42LEX-5026 / FT2C LED TV with V420HJ2-P01 LCD, 42 "(107 cm) diagonal size in 16: 9 format. The required screen brightness of 250 cd / m² is provided by LED backlighting. The ratio of maximum brightness to minimum ( contrast ratio) is 4000: 1. The LED display is implemented in the model’s display technology, and the TV’s design and technical capabilities provide for viewing broadcasts and films in high quality HD at a resolution of 1920x1080 pixels in a graphic resolution of 1080p (Full HD) standard.
42LEX-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.
The power of the sound speaker system 16 W (2x8 W) is provided by 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 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 stand 911x563x209 mm, Without stand 911x522x90 mm.
TV Weight: 8.8 kg.
Attention! The BBK 42LEX-5026 / FT2C LED TV panel V420HJ2-P01 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.