Technical description and composition of the BBK LT3709 TV, panel type and applicable modules. The composition of the modules.BBK
Model: LT3709
Panel: T370XW01 rev. 0
Power Supply (PSU): MLT070A
PWM Power: ML4800CS, FAN7601, LM358
MOSFET Power: 20N60, 9N50, 5N60
MainBoard: 200-100-GF328-FH // 200-107-GK371XP-CH
IC MainBoard: CPU: SVP EX52, M30620SPGP SAA7117AH, Eeprom: 24c64, Flash: A29040B
Technical Specifications LT3709S
BBK LT3709
General recommendations for repairing TV LCD
Possible manifestations of defects
- BBK LT3709 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.
Often in such cases, the MLT070A power module is faulty. It is necessary to measure its secondary output voltages, and in case of their absence, check the serviceability of the power switches (20N60, 9N50, 5N60) 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.
Mos-Fet keys used in switching power supplies usually fail due to a malfunction of other elements that can put it out of operation in key mode or provoke an excess of the maximum current or voltage. It can be supply, damper circuits, or elements of OOS (negative feedback) stabilization. The reason for the breakdown of the power key can be PWM (MLW) ML4800CS, FAN7601, LM358. It is checked only by replacement with a known good one.
- 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.
These manifestations can be triggered by a power module, or by defects in the inverter, as well as a distortion of the currents in the lamps due to their uneven wear. If all the electrolytic capacitors of the filter according to the inverter power supply are serviceable, you should make sure that the lamps are working, then you need to check the converter keys and the secondary windings of the transformers.
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 during work, 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 200-100-GF328-FH 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). 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: SVP EX52, M30620SPGP SAA7117AH, Eeprom: 24c64, Flash: A29040B and other possible faulty components. Malfunctions associated with the application of BGA soldering technologies are usually easily diagnosed by the heating method.
Once again, remind users! Attempts to self-repair a BBK LT3709 TV without the appropriate qualifications and necessary experience can lead to its complete non-repairability!
The appearance of the MainBoard 200-100-GF328-FH is shown in the figure below:200-100-GF328-FH
200-100-GF328-FH can be used in TVs:
BBK LT3709 (Panel T370XW01 rev. 0), BBK LT4005S (Panel LTA400WT-L11).
The appearance of the power supply
Main features of the BBK LT3709 device:
Installed matrix (LCD panel) T370XW01 rev. 0.
The necessary supply voltages for all nodes of the TV BBK LT3709 are generated by the MLT070A power module, or its analogs using microchips ML4800CS, FAN7601, LM358 and power switches of the type 20N60, 9N50, 5N60.
MainBoard - the main board (motherboard) is a 200-100-GF328-FH module using CPU chips: SVP EX52, M30620SPGP SAA7117AH, Eeprom: 24c64, Flash: A29040B and others.
Additional technical information about the panel:
Brand: AUO
Model: T370XW01 V9
Type: a-Si TFT-LCD, Panel
Diagonal size: 37 inch
Resolution: 1366x768, WXGA
Display Mode: Normally Black, Transmissive
Active Area: 819.6x460.8 mm
Lamp Type: CCFL
LCD TV BBK LT3709S with LCD T370XW01, diagonal size 37 "(94 cm) 16: 9 format. The brightness of the screen is 500 cd / m² backlight fluorescent lamps CCFL (EEFL). The ratio of maximum brightness to minimum (contrast) is 1000: 1. It is possible to view images in high quality HD at a resolution of 1366x768 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 the standard ah 480i, 480p, 576i, 576p, 720p, 1080i.
The power of the sound speaker system 20 W (2x10 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 x2, audio x5, component, SCART x2, RGB, VGA, HDMI x2. 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, 1280x1024, 1360x768.
The power consumed by the TV in the operating mode from the network is 300 watts.
Overall dimensions: 927x733x270 mm.
TV Weight: 26.5 kg.
Attention! The T370XW01 V.1 panel of the BBK LT3709S 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!