Technical description and composition of the BBK LED2455FDT TV, type of panel and applicable modules. The composition of the modules.BBK LED
Model: LED2455FDT
Chassis / Version: L0M05
Panel: LC230EUE (TD) (A1)
T-CON: LM230WF5-TLD1 P / N: 6870S-1120A
LED driver (backlight): LDA15-63V240K
MOSFET LED driver: 12N10L
Power Supply (PSU): FSE060A Rev: 1.1
PWM Power: LD7535 (PWM 6 pin)
MainBoard: L0M05
IC MainBoard: CPU: MSD309PX-LF-Z1; Spi Flash: 25Q32 Ram: W9751G6JB-25; YD1517P, MP1484EN
Tuner: R620D
Control: IR: 55S_IR (00)
Technical Specifications LED2455FDT
BBK LED2455FDT
General repair guidelines for TV LCD LED
If the TV does not turn on, no control lights are on or blinking, there are no sounds when you turn on, and there is not the slightest sign of operability - the most likely malfunction is in the power module. In the general case, first of all, it is necessary to check the electrolytic capacitors of the secondary rectifier filters and the fuse at the input of the network. If it is broken, then you should check for breakdown of the PN junctions of the rectifier bridge diodes and the key transistor of the converter, which can either be on a separate radiator or integrated with a PWM controller in a common chip. Possible options.
If a breakdown of the power switch is detected, it should be remembered that in a switching power supply (IIP) it does not fail by itself without any reasons that should be sought by checking other elements of the primary circuit - electrolytic capacitors, PWM controller LD7535 (6 pin) , which can be checked only by replacement, as well as other semiconductor elements (diodes, transistors, zener diodes).
If there is no image when you turn on the BBK LED2455FDT, or it appears and immediately disappears, but there is sound, most likely there is a malfunction in the backlight LED circuit of the LC230EUE (TD) (A1) panel, or in the LED node of the driver-converter of their power supply.
In most cases of lack of backlight, it becomes necessary to disassemble the panel in order to check the LEDs, connectors, loops and all contact connections. If one or several LEDs does not work in one line, therefore, they are broken and should be replaced.
It is impossible to check the line of series-connected LEDs without a special current source, and for this purpose it is not safe to use any voltage sources above 12V for them. Then it remains only to open the panel and check each LED separately. Usually, Chinese 9V-powered multimeters light up a single 3-volt LED, if you connect the probes in the forward direction, the red probe to the anode, and the 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.
In cases of attempts to repair the motherboard L0M05 (00, it is necessary to check the operability of the linear stabilizers and power converters of its microcircuits and, if possible, update the software.) BGA chips can sometimes be diagnosed with local heating.
In cases of complex repairs of MB (SSB) and in the presence of the necessary skills and equipment, sometimes it may be necessary to replace its Cpu chips: MSD309PX-LF-Z1; Spi Flash: 25Q32 Ram: W9751G6JB-25; YD1517P, MP1484EN and other possible defective components. Malfunctions associated with the application of BGA soldering technologies are usually easily diagnosed by the heating method.
Before changing the R620D 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 terminals of the tuner and check the software for correctness. The pulses of the data exchange of the tuner with the processor can be controlled by an oscilloscope
Attention to users! Self-repair of the BBK LED2455FDT TV without the appropriate qualifications and experience can lead to its complete non-repairability!
Service Manual with Schematic Diagram 82 pages of 2011 on the model LED1955DT, LED2255FDT, LED2455FDT
The appearance of the MainBoard L0M05 is shown in the figure below:The MainBoard L0M05 uses the MSD309B processor, a BGA-based DDRAM random access memory (RAM) and an SPI Flash ROM of type 25Q32 (4Mb).
It is advisable to start the repair of the motherboard by checking the voltage converters and linear stabilizers necessary to provide power to the nodes in the operating and standby modes. The processor core is powered by + 1.5V. Also, the processor voltage requires + 2.5V and + 3.3V.
If the display backlight is working properly and there is no image, it is necessary to check the panel power (depending on the type, + 5V or + 12V), which is more convenient to measure directly on the LVDS connector. If, in the presence of all the supply voltages, the TV does not enter the operating mode, does not respond to the Remote Control and control buttons, you should update the SPI Flash firmware.
L0M05 can be used in TVs:
BBK LED1955DT (Panel V185B1-LE1 Rev.C1), BBK LED2275FDT (Panel V215H1-LE1 REV.C1), BBK LED2475FDT (Panel LC230EUE (TD)(A1)), BBK LEM1968DT Ver1 (Panel V185B1-LE1 Rev.C1), BBK LEM2488FDT (Panel LC230EUE), BBK LEM1988DT (Panel V185B1-LE1 Rev.C1 CMO), BBK LED2455FDT (Panel LC230EUE (TD)(A1)).
The appearance of the power supply
Main features of the BBK LED2455FDT device:
Installed matrix (LED-panel) LC230EUE (TD) (A1).
The matrix control uses the Timing Controller (T-CON) LM230WF5-TLD1.
The LED driver LDA15-63V240K is used to power the backlight LEDs. As power elements of the LED driver, keys of the 12N10L type are used.
The necessary supply voltages for all nodes of the BBK LED2455FDT TV are generated by the FSE060A power module or its analogs using LD7535 microcircuits (PWM 6 pin).
MainBoard - the main board (motherboard) is a L0M05 module, using Cpu microcircuits: MSD309PX-LF-Z1; Spi Flash: 25Q32 Ram: W9751G6JB-25; YD1517P, MP1484EN and others.
The R620D tuner provides TV reception and channel tuning.
Information from an alternative source:
BBK LED2455FDT
Panel Type (Matrix): LC230EUE (TD) (A1)
Motherboard: LOM05 (00)
T-con: LM230WF5-TLD1 P / N: 6870S-1120A (not removable)
LED Driver: LDA15-63V240K
PSU: FSE060A Rev: 1.1
Remote control: RC2252
Additional technical information about the panel:
Brand: LG Display
Model: LC230EUE-TDA1
Type: a-Si TFT-LCD, Panel
Diagonal size: 23.0 inch
Resolution: 1920x1080, FHD
Display Mode: TN, Normally White, Transmissive
Active Area: 509.184x286.416 mm
Surface: Antiglare, Hard coating (3H)
Brightness: 250 cd / m²
Contrast Ratio: 1000: 1
Display Colors: 16.7M (8-bit)
Response Time: 1.3 / 3.7 (Tr / Td)
Frequency: 60Hz
Lamp Type: 2 strings WLED Without Driver
Signal Interface: LVDS (2 ch, 8-bit), 30 pins
Voltage: 5.0V
BBK LED2455FDT LED TV with LC230EUE LCD, 24 "(61 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 1000: 1 This model uses side illumination from Edge LEDs.The design and technical capabilities of the TV include watching programs and movies in high quality HD at a resolution of 1920x1080 pixels in graphic resolution according to the standard 1080p (Full HD). Input high-frequency or video signal can be processed in analogue systems PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Supported media file formats: MP3, WMA, MPEG4, MKV, VideoCD, SVCD, JPEG.
The power of the acoustic system of sound 6 W (2x3 W) provide 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, audio x2, SCART, RGB, VGA, HDMI x2, USB. An output for connecting headphones is provided. To connect a computer or laptop to this TV model, a VGA (D-Sub 15) connector is used on the TV case, this interface supports resolutions: 640x480, 800x600, 1024x768. The digital tuner is capable of receiving television channels in DVB-T MPEG4 standards.
The power consumed by the TV in the operating mode from the network is 40 watts.
Overall dimensions: 589x491x150 mm.
The mass of the TV: 4.4 kg.
Attention! The BB2 LED2455FDT LCD panel LC230EUE (TD) (A1) 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.
