Technical description and composition of the BBK LEM2685FDTG TV, panel type and applicable modules. The composition of the modules.BBK LED
Model: LEM2685FDTG
Chassis / Version: MSD309
Panel: V260H1-LE8 Rev. C1
T-CON: V260H1-XC03 (V260H1-P03 Rev. C2)
LED driver (backlight): TV2631-ZC02-01 (B)
PWM LED driver: RT8566
MOSFET LED driver: B6010D
Power Supply (PSU): TV2632-ZC02-02 (A)
PWM Power: OB2263
MainBoard: MSDV3209-ZC01-01 (D) 2011.02.25
IC MainBoard: CPU: MSD309PT, SPI Flash: MX25L6406EMI, Audio: TPA3113D2
Tuner: DT58WT-3RB-E
Technical Specifications LEM2685FDTG
BBK LEM2685FDTG
General repair guidelines for TV LCD LED
Possible manifestations of defects
- The BBK LEM2685FDTG TV does not turn on at all. The control lights do not light or flash. The TV on the remote control and the control panel buttons do not respond.
With similar manifestations, in some cases, the TV2632-ZC02-02 power module turns out to be faulty. It is necessary to measure its output voltages, and in case of their absence, check the operability of the power switches of the converters and rectifier diodes for the probability of a short circuit.
In the event of breakdowns in the secondary circuits of the converter, it can usually fail in short circuit mode, and in the event 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 circuits OB2263 are usually checked by replacing with new, or obviously working.
- There is no image, there is sound, it responds to the remote control. Or the image may appear for a second when turned 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 will be 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 motherboard MSDV3209-ZC01-01 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 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: MSD308PX, SPI Flash: MX25L6406EMI and other possible faulty components. Malfunctions associated with the application of BGA soldering technologies are usually easily diagnosed by the heating method.
Before changing the DT58WT-3RB-E tuner, if it is not possible to tune to television channels, 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
Once again, we remind TV users: you should not make attempts to repair it yourself without the appropriate knowledge, experience and the necessary qualifications! Entrust repair to professionals with sufficient experience in the field of repair of electronic equipment.
SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> BBK LEM2685FDTG Chassis MSD309
To reduce the backlight current in LED drivers with an RT8566 controller, it is necessary to proportionally increase the resistance of the resistor from terminal 2 (RISET) to the housing. The current in each channel is determined from the 543.6 / Rset ratio.
Repair MainBoard
The appearance of the MainBoard MSDV3209-ZC01-01 is shown in the figure below:
MainBoard MSDV3209-ZC01-01 uses a multifunctional microprocessor of the type MSD309PX or MSD308PX with an integrated scaler. Two RAM chips W9751G6IB are used as RAM. SPI Flash MX25L6406EMI-12G is made in the SOP-16 (16 pin) package.
It is advisable to start the repair of the motherboard by checking the voltage + 5V standby mode. In the operating mode, it is necessary to check the operability of linear stabilizers and power converters of the processor, memory, panel and other components of the board.
MSDV3209-ZC01-01 can be used in TVs:
BBK LEM3281FDT (Panel V315B1-LE9 REV.C1), BBK LEM3285FDTG (Panel V315H4-LE7 REV.C1), BBK LEM1949DT (Panel HT185WX3-100), BBK LEM3248DT (Panel V315B1-LE7 REV.C1), BBK LEM2665FDTG (Panel V260H1-LE8), BBK LEM3249FDT (Panel V315H4-LE8), BBK LEM2449FDT (Panel M236MWF7), BBK LEM3282DT (Panel V315B1-LEA), MYSTERY MTV-4018LW (Panel T390HVN01.0), MYSTERY MTV-4022LW (Panel M390HJ1-P01), MYSTERY MTV-4214LW (Panel T420HW08 V.5 FHD), MYSTERY MTV-3214LW (Panel V315H4-LE2 Rev.C1), MYSTERY MTV-4217LW (Panel T420HW09 V.9 (FHD)), MYSTERY MTV-3220LW (Panel V315H4-LE7).
The appearance of the power supply
Main features of the BBK LEM2685FDTG device:
Installed matrix (LED-panel) V260H1-LE8 Rev. C1.
The matrix control uses the Timing Controller (T-CON) V260H1-XC03.
To power the backlight LEDs, the TV2631-ZC02-01 LED driver is used, controlled by the RT8566 PWM controller. As power elements of the LED driver, keys of the type B6010D are used.
The necessary supply voltages for all nodes of the TV BBK LEM2685FDTG are generated by the TV2632-ZC02-02 power module, or its analogs using OB2263 microcircuits.
MainBoard - the main board (motherboard) is an MSDV3209-ZC01-01 module, using CPU chips: MSD309PT, SPI Flash: MX25L6406EMI, Audio: TPA3113D2 and others.
Tuner DT58WT-3RB-E provides the reception of television programs and tuning to channels.