Technical description and composition of the BBK 32LEX-5024 TV, type of panel and applicable modules. The composition of the modules.BBK LED
Model: 32LEX-5024 / T2C
Chassis / Version: CV338H-T42
Panel: TH32YS1704D0089
LED driver (backlight): integrated into MainBoard
PWM LED driver: BIT3267
MOSFET LED driver: AOD4454
Power Supply (PSU): integrated into MainBoard
PWM Power: PF6000AG (PWM SOT23-6)
MOSFET Power: 7R600
MainBoard: CV338H-T42
IC MainBoard: MSD6A338, MSB102KT, W25Q16DVSSIG, MP7752
Tuner: R842
Specifications 32LEX-5024 / T2C
BBK 32LEX-5024
General repair guidelines for TV LCD LED
Possible manifestations of defects
- BBK 32LEX-5024 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.
First of all, in such cases, you should verify the operability of the common switching power supply (IIP) - AC / DC voltage converter of the mains voltage. All source elements in this TV model are located on the MainBoard CV338H-T42 main board. Then it is necessary to measure its output voltages and, in case of their complete or partial absence, it is necessary to check the serviceability of power switches (7R600) and rectifier diodes of the converters for the presence of a possible short circuit.
In case of breakdowns in the secondary circuits of the converter, it can usually fail in short circuit mode, and in case of a short circuit in the power elements of the primary circuit, the mains fuse or current sensor at the source of the key most often breaks.
The breakdown of Mos-Fet keys used in pulsed sources is often caused by malfunctions of other elements, for example, in the power supply circuit of a PWM controller, in frequency-setting or damping circuits, as well as in Negative Stabilization Feedback. PWM (PWM) PF6000AG (PWM SOT23-6) microcircuits are usually checked by replacing with new ones, or obviously working.
- There is no image, there is sound, it responds to the remote control, the channels are switched. In some cases, the image appears when you turn on and immediately disappears.
The most likely in these cases is a malfunction of the LED backlight. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
It is impossible to check the LED line for breaks without disassembling the panel with a multimeter or tester. For these purposes, it is necessary to open all series-connected PN junctions and a voltage of the order of tens of volts is required, and ideally, a current source. Having disassembled the panel, it is necessary to check each LED separately. Chinese multimeters, as a rule, light up a single 3-volt LED in the forward direction. In the case of using dual 6-volt LEDs, the PN junction of its protective zener diode can serve as a health indicator. In faulty LEDs, the 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 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). In cases of attempts to repair the MB (SSB) board, it is necessary to check the health of its elements - MSD6A338, MSB102KT, W25Q16DVSSIG, 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).
Before changing the R842 tuner, if it is not possible to tune to television channels, you should make sure that there are supply voltages that must be measured at the corresponding tuner pins and check the software for correctness. The pulses of the data exchange of the tuner with the processor can be controlled by an oscilloscope
Owners and users of the BBK 32LEX-5024 TV should remember that self-repair without special knowledge, skills and qualifications can be fraught with negative consequences that can lead to complete non-repairability of the device!
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 32LEX-5024 device:
Installed matrix (LED-panel) TH32YS1704D0089.
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 PF6000AG (PWM SOT23-6) microcircuits and 7R600 type power switches.
MainBoard - the main board (motherboard) is a CV338H-T42 module, using microchips MSD6A338, MSB102KT, W25Q16DVSSIG, MP7752 and others.
The R842 tuner provides TV reception and channel tuning.
BBK 32LEX-5024 / T2C LED TV with 32 "(81 cm) 32: 9 LCD diagonal TH32YS1704D0089 LCD display. The required brightness of the screen is 250 cd / m² thanks to LED backlighting. The ratio of maximum brightness to minimum (contrast) is 3000: 1. The LED display backlighting technology is implemented in the model’s display technology.
32LEX-5024 / T2C 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 737x473x212 mm, Without stand 737x435x83 mm.
The mass of the TV: 6.2 kg.
Attention! The panel of the TH32YS1704D0089 BBK 32LEX-5024 / T2C 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.
