Technical description and composition of the BBK LT1902S TV, panel type and applicable modules. The composition of the modules.BBK
Model: LT1902S
Chassis / Version: Ver1.0
Panel: M190A1-P0A
Inverter (backlight): LK-PI190414CF
PWM Inverter: BIT3713 (16)
MOSFET Inverter: AO 4606 (8)
Trans Inverter: LKT001 CFD 1004
Power Supply (PSU): LK-P190414CF
PWM Power: GR8876 (8)
MOSFET Power: 8N60
Mainboard: CV7050LA
IC MainBoard: TDA1517P, TDA9886TS, BM1084,
Tuner: F21WT-3BAR-E
BBK
Model: LT1902S
Chassis / Version: HD_T7050H_V1.3A 2009-7-7 (sticker1: HD0911F468
Panel: M190PW01 V0
Inverter (backlight): DSC03494
Power Supply (PSU): DSC03494
MainBoard: HD_T7050H_V1.3A 2009-7-7 (sticker1: HD0911F468)
IC MainBoard: SPV7050P, T24C32A, EN25T80-75QCP, CD1517CP, TDA9886TS
Tuner: TNF931D-BFR1
Technical Specifications LT1902S
BBK LT1902S
General recommendations for repairing TV LCD
Possible malfunctions
- BBK LT1902S does not turn on at all and does not show any signs of operability. Does not blink indicators and does not respond to control buttons.
In most of these cases, the main switching power supply DSC03494 is faulty. It is necessary to measure its secondary output voltages, 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 mains fuse usually breaks.
The breakdown of Mos-Fet keys used in pulsed sources is often caused by malfunctions of other elements, for example, power supply, frequency-setting, damper ... as well as elements of the Negative Stabilization Feedback. The PWM chip can also cause a malfunction of the power switch of the converter and is checked by replacement.
- 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 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 inverter. If all the electrolytic capacitors of the filter according to the power supply of the inverter are working, make sure that the lamps are working, then you need to check the converter keys and the secondary windings of the transformers.
Sometimes, for diagnostic purposes, inverter protection must be disabled. In such cases, special care must be taken during work, and the protection circuits should be restored immediately after the repair is completed.
- The indicator on the front panel blinks, the TV does not turn on in the operating mode, it does not respond to the remote control.
Repair or diagnostics of the motherboard HD_T7050H_V1.3A should begin by checking the stabilizers and power converters needed to power the microcircuit and matrix. If necessary, update or replace the software (software). In cases of attempts to repair the MB board (SSB), it is necessary to check the health of its elements - SPV7050P, T24C32A, EN25T80-75QCP, CD1517CP, TDA9886TS 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).
If you suspect a malfunction of the TNF931D-BFR1 tuner, first of all, you need to verify the correctness of the software, as well as the presence of the necessary voltage levels and pulses of data exchange with the processor via the I2C bus at the corresponding terminals of the tuner.
Once again, remind users! Attempts to self-repair a TV BBK LT1902S without the appropriate qualifications and the necessary experience can lead to its complete non-repairability!
SCHEMATIC / MANUAL -------------> BBK LT1902S, LT2202S
The appearance of the MainBoard CV7050LA is shown in the figure below:CV7050LA
CV7050LA can be used in TVs:
BBK LT1902S (Panel M190A1-P0A), BBK LT2202S (Panel M216H1-P01), BBK LT2428HD (Panel V236H1-P01 HK236WLCM-CH03H), BBK LT2428S (Panel V236H1-P01), FUSION FLTV-19W6 (Panel M190A1-P0A), IZUMI TL26H615B (Panel M260TWR1).
Main features of the BBK LT1902S device:
Installed matrix (LCD panel) M190PW01 V0.
To power the backlight used inverter DSC03494.
The formation of the necessary supply voltages for all nodes of the BBK LT1902S TV is carried out by the power module DSC03494, or its analogs.
MainBoard - the main board (motherboard) is an HD_T7050H_V1.3A module, using chips SPV7050P, T24C32A, EN25T80-75QCP, CD1517CP, TDA9886TS and others.
The TNF931D-BFR1 tuner provides TV reception and channel tuning.
Additional technical information about the panel:
Brand: AUO
Model: M190PW01 V0 (0H 0J)
Type: a-Si TFT-LCD, Panel
Diagonal size: 19.0 inch
Resolution: 1440x900, WXGA +
Display Mode: TN, Normally White, Transmissive
Active Area: 408.24x255.15 mm
Surface: Antiglare, Hard coating (3H)
Brightness: 300 cd / m²
Contrast Ratio: 1000: 1
Display Colors: 16.7M (6-bit + Hi-FRC), CIE1931 72%
Response Time: 3.6 / 1.4 (Tr / Td)
Frequency: 60Hz
Lamp Type: 4 pcs CCFL Without Driver
Signal Interface: LVDS (2 ch, 8-bit), 30 pins
Voltage: 5.0V
BBK LT1902S LCD TV with M190PW01 LCD, 19 "(48 cm) diagonal 16:10 format. Screen brightness of 300 cd / m² is provided by CCFL (EEFL) fluorescent lamps. The ratio of maximum brightness to minimum (contrast) is 600: 1. It is possible to view images in high quality HD at a resolution of 1440x900 pixels in the standard of graphic decomposition 720p (HD Ready). The input high-frequency or video signal can be processed in analog systems PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in standard ah 480i, 480p, 576i, 576p, 720p, 1080i. Stereo sound is realized by two built-in speakers. NICAM STEREO audio processing system is used.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, audio x2, S-Video, SCART, RGB, VGA, HDMI. 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 power consumed by the TV in the operating mode from the network is 60 watts.
Overall dimensions: 530x440x153 mm.
Attention! The M190PW01 V0 panel of the BBK LT1902S LCD TV is its most expensive component.
Avoid hitting the glass and exerting pressure on the screen to avoid permanent damage to the LCD panel!
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, audio x2, S-Video, SCART, RGB, VGA, HDMI. 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 power consumed by the TV in the operating mode from the network is 60 watts.
Overall dimensions: 530x440x153 mm.
Attention! The M190PW01 V0 panel of the BBK LT1902S LCD TV is its most expensive component.
Avoid hitting the glass and exerting pressure on the screen to avoid permanent damage to the LCD panel!