Technical description and composition of the TV BBK 24LEM-1027, type of panel and applicable modules. The composition of the modules.BBK LED
Model: 24LEM-1027 / T2C
Chassis / Version: CV512L-Q24
Panel: CX236DLEDM
LED driver (backlight): integrated into MainBoard
PWM LED driver: BIT3367A
MOSFET LED driver: MMBT3904
Power Supply (PSU): integrated into MainBoard
PWM Power: LD5530
MOSFET Power: 70R900P
MainBoard: CV512L-Q24
IC MainBoard: CPU: S2T512, SPI Flash: W25Q64, AUDIO: YD1517P
Tuner: CDT-9NT372-RD60
Technical Specifications 24LEM-1027 / FT2C
BBK 24LEM-1027
General repair guidelines for TV LCD LED
Possible malfunctions
- The BBK 24LEM-1027 TV does not turn on and does not show any signs of turning on, it does not respond to the control buttons or to the remote control.
In such cases, the AC / DC converter of the mains voltage, which is combined with the main board CV512L-Q24, is often faulty. It is then necessary to measure its output voltages and, if they are absent, you should check the power switches (70R900P) and the rectifier diodes of the converters for the probability of a short circuit.
In case of any breakdown of semiconductors in the secondary circuits, the converter can usually work normally in emergency short circuit mode. There are no output voltages. And with a short circuit in the power elements of the primary circuit, as a rule, the mains fuse breaks and less often the current sensor at the source of the key.
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) LD5530, if they do not have visible damage to the case and open fault between the terminals, are usually checked by replacement.
- 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.
As a rule, in such cases there is no display backlight. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
When trying to detect a break in the LED lines, it should be taken into account that it is difficult to do this without disassembling the panel. For example, a current source is needed to open PN junctions connected in series.
- The TV does not turn on, the indicator indicates standby or operating mode, or blinks.
Repair or diagnostics of the CV512L-Q24 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). Complex repair of MB (SSB) is possible only in the conditions of a service center with the necessary equipment. Checking or replacing CPU elements: S2T512, SPI Flash: W25Q64, AUDIO: YD1517P requires the necessary training and professional skills to repair modules at the component level. Problems associated with the use of BGA soldering technologies can sometimes be diagnosed by warming up.
If the TV works normally from external devices, but does not tune to television channels, the CDT-9NT372-RD60 tuner 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.
It should be remembered! Attempts to independently repair the BBK 24LEM-1027 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!
SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> MainBoard CV512L-Q24
FIRMWARE FOR SPI FLASH -----------> BBK 24LEM-1027/T2C, Main: CV512L-Q24, Panel: CX236DLEDM
The appearance of the MainBoard CV512L-Q24 is shown in the figure below:CV512L-Q24
Main features of the BBK 24LEM-1027 device:
Installed matrix (LED-panel) CX236DLEDM.
To power the backlight LEDs, a converter is used, combined with the main board CV512L-Q24, controlled by the BIT3367A PWM controller. As power elements of the LED driver, keys of the type MMBT3904 are used.
The power module is combined with the MainBoard and is designed according to a flyback AC / DC voltage converter using LD5530 microcircuits and 70R900P type power switches.
MainBoard - the main board (motherboard) is a CV512L-Q24 module, using CPU chips: S2T512, SPI Flash: W25Q64, AUDIO: YD1517P and others.
The tuner CDT-9NT372-RD60 provides the reception of television programs and tuning to channels.
BBK 24LEM-1027 / FT2C LED TV with CX236DLEDM LCD, 24 "(61 cm) diagonal of 16: 9 format. The required brightness of the screen is 200 cd / m² thanks to LED backlighting. The ratio of maximum brightness to minimum (contrast) is 3000: 1. The LED display technology is implemented in the model’s display technology. multimedia files: MP3, WMA, MKV, JPEG.
The power of the acoustic system of sound 6 W (2x3 W) provide two speakers. It uses a NICAM stereo signal processing system and Sound Surround.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, component, VGA, HDMI, USB. An output for connecting headphones is provided. A digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
Overall dimensions: with a support 557x367x165 mm, without a support 557x334x79 mm.
Mass of the TV: 2.4 kg.
Attention! The CX236DLEDM panel of the BBK 24LEM-1027 / 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.