Technical description and composition of the BBK LT2002S TV, panel type and applicable modules. The composition of the modules.BBK
Model: LT2002S
Chassis / Version: Ver2.20
Panel: LC201V02-SDB1
Inverter (backlight): 5INV607-3
PWM Inverter: VP1048FM (28)
MOSFET Inverter: AO4822 (8)
Power Supply (PSU): 52008-2
PWM Power: TOP249Y
MainBoard: MAIN_PCB
IC MainBoard: MST518VA, TVP5146, STV8216
Tuner: JS-5B2 / 121
Control: LT2002S, LT117-02
Technical specifications LT2002S
BBK LT2002S
General recommendations for repairing TV LCD
Possible manifestations of defects
- The BBK LT2002S TV does not turn on and does not show any signs of operability at all. There is no reaction to either the remote control or the front panel control buttons.
In such cases, the fault should be sought first in the 52008-2 power supply module. It is necessary to measure the secondary output voltage, and in case of their absence, check the serviceability of the power switches of the converters and rectifier diodes for a short circuit.
In case of breakdowns in the secondary circuits, the converter can operate in a short circuit mode, and during short circuit in the elements of the primary circuit, the main fuse usually breaks.
The breakdown of Mos-Fet keys used in pulsed sources is often caused by malfunctions of other elements, for example, power, frequency-setting, damper ... as well as elements of the Negative Stabilization Feedback. PWM chip TOP249Y can also cause a malfunction of the power switch of the converter and is checked by replacement.
- There is no image, but there is sound and reaction to the remote control. Or for a second, the image may appear immediately after switching on.
The defect can be caused by problems in the nodes or elements of the backlight of the display, or in the power supply of the lamps or the inverter.After checking all the electrolytic capacitors of the filters that are involved in the power supply of the inverter, you must ring in its converter power keys for breakdown and secondary windings of transformers for an open.
If in diagnosing a malfunction, it is necessary to disable the inverter protection, there is a risk of failure of the power elements of the inverter, and special care is required when working, and after they are finished, it is necessary to restore the protection circuits for further safe operation of the TV by the owner in normal mode.
- The indicator blinks or lights constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the MAIN_PCB 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 - MST518VA, TVP5146, STV8216. Defective components should be replaced.
If a JS-5B2 / 121 tuner is suspected of malfunction, first of all, it is necessary to verify the correctness of the software, as well as the presence of the necessary supply voltage levels and data exchange pulses with the processor via the I2C bus on the corresponding tuner pins.
TV users and owners need to remember that attempts to self-repair a BBK LT2002S TV without the appropriate qualifications and necessary experience can lead to serious negative consequences!
Main features of the BBK LT2002S device:
Installed matrix (LCD panel) LC201V02-SDB1.
A 5INV607-3 inverter is used to power the backlight lamps; it is controlled by the PWM controller VP1048FM (28). As power elements of the inverter, keys of the type AO4822 (8) are used.
The necessary supply voltages for all nodes of the BBK LT2002S TV are generated by the 52008-2 power module or its analogs using TOP249Y microcircuits.
MainBoard - the main board (motherboard) is a MAIN_PCB module, using microchips MST518VA, TVP5146, STV8216 and others.
The JS-5B2 / 121 tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: LG.Philips LCD
Model: LC201V02-SDB1
Type: a-Si TFT-LCD, Panel
Diagonal size: 20.1 inch
Resolution: 640x480, VGA
Display Mode: IPS, Normally Black, Transmissive
Active Area: 408x306 mm
Surface: Antiglare, Hard coating (3H)
Brightness: 450 cd / m²
Contrast Ratio: 800: 1
Display Colors: 16.7M (8-bit)
Response Time: 12/13 (Tr / Td)
Frequency: 60Hz
Lamp Type: 6 pcs CCFL Without Driver
Signal Interface: CMOS (1 ch, 8-bit), 41 pins
Voltage: 12.0V
BBK LT2002S LCD TV with LCD display LC201V02-SDB1, diagonal size 20 "in 4: 3 format. The brightness of the screen is 450 cd / m² with CCFL (EEFL) fluorescent lamps. The ratio of maximum brightness to minimum (contrast) is 800: 1. The input high-frequency or video signal can be processed in analog systems PAL, SECAM, NTSC. Graphic processing and digital signal generation takes place in the standards 480i, 480p, 576i.
The power of the acoustic system of sound 6 W (2x3W) 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, S-Video, SCART, RGB.
The power consumed by the TV in the operating mode from the network is 65 watts.
Overall dimensions: 620x450x202 mm.
The mass of the TV: 7.6 kg.
Attention! The BBK LT2002S LCD TV panel LC201V02-SDB1 is its most expensive component.
Avoid hitting the glass and exerting pressure on the screen to avoid permanent damage to the LCD panel!