Sunday 5 April 2020

REPAIR / SERVICING TV AKAI LTA-15A15M

Technical description and composition of the AKAI LTA-15A15M TV, panel type and applicable modules. The composition of the modules.
AKAI
Model: LTA-15A15M
Chassis / Version: AS-MST6M181VS-LE1
Panel: LTA150XH-L06
Inverter (backlight): AYI240408 (AYI240409)
PWM Inverter: TL494 (16)
MOSFET Inverter: ME494 (8)
Trans Inverter: GIVTEEL190002 121017
Power Supply (PSU): DC12030011A 12V 3A
PWM Power: OB2263 (PWM SOT23-6)
MainBoard: AS-MST6M181VS-LE1
IC MainBoard: CFeon Q32B0104HIP (8), YD1517P (18), FR9888 (8) = MP1484EN
Tuner: ET-6N1E-CF101R
Technical Specifications LTA-15A15M
AKAI LTA-15A15M
General recommendations for repairing TV LCD
Possible malfunctions
- The AKAI LTA-15A15M TV does not turn on. There are no signs of operability. The indicators on the front panel do not shine and do not blink, and the remote control and control buttons do not respond.
Failure in such cases should be sought in the DC12030011A power supply circuits. It is necessary to measure the secondary output supply 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 a 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, but there is sound and reaction to commands from the remote control. Or the image appears immediately after turning on and 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 the inverter.After checking all the electrolytic capacitors of the filters that are involved in the power supply to the inverter, you must ring in its converter power keys for breakdown and secondary windings of transformers for an open.
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 TV does not turn on, does not respond to the remote control. The indicator blinks or signals standby mode.
Repair or diagnostics of the AS-MST6M181VS-LE1 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 attempts to repair the MB (SSB) board, it is necessary to check the health of its elements - cFeon Q32B0104HIP (8), YD1517P (18), FR9888 (8) = MP1484EN 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 the TV works normally from external devices, but does not tune into television channels, the tuner ET-6N1E-CF101R may be malfunctioning. In such cases, first of all, you should make sure that there are supply voltages at its corresponding conclusions. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus. Sometimes the cause of the inoperability of the tuner may be a software failure.
It should be remembered! Attempts to independently repair the AKAI LTA-15A15M TV, in the absence of the necessary qualifications and experience, are categorically not recommended and are fraught with negative consequences, up to the complete non-repairability of the device!




Repair MainBoard
The appearance of MainBoard AS-MST6M181VS-LE1 is shown in the figure below:
AS-MST6M181VS-LE1
AS-MST6M181VS-LE1 can be used in TVs:
AKAI LTA-15A15M (Panel LTA150XH-L06), AKAI LEA-22A08G (Panel LM215WF4 (TL) (E7)), AKAI LEA-19A08G (Panel LM185WH2-TLA1).
The appearance of the power supply
Key Features of the AKAI LTA-15A15M:
Installed matrix (LCD panel) LTA150XH-L06.
AYI240408 inverter is used to power the backlight lamps; it is controlled by the TL494 PWM controller (16). A GIVTEEL190002 121017 transformer is installed in the inverter converter. Keys of type ME494 (8) are used as power elements of the inverter.
The necessary supply voltages for all nodes of the AKAI LTA-15A15M TV are generated by the DC12030011A power supply module or its analogs using OB2263 microcircuits (PWM SOT23-6).
MainBoard - the main board (motherboard) is an AS-MST6M181VS-LE1 module, using cFeon Q32B0104HIP (8), YD1517P (18), FR9888 (8) = MP1484EN and others.
The ET-6N1E-CF101R tuner provides television reception and channel tuning.
Additional technical information about the panel:
Brand: SAMSUNG
Model: LTA150XH-L06
Type: a-Si TFT-LCD, Panel
Diagonal size: 15.0 inch
Resolution: 1024x768, XGA
Display Mode: TN, Normally White, Transmissive
Active Area: 304.1x228.1 mm
Surface: Antiglare (Haze 25%), Hard coating (3H)
Brightness: 400 cd / m²
Contrast Ratio: 400: 1
Display Colors: 16.2M (6-bit + FRC), CIE1931 65%
Response Time: 5/20 (Tr / Td)
Frequency: 60Hz
Lamp Type: 4 pcs CCFL Without Driver
Signal Interface: LVDS (1 ch, 8-bit), 20 pins
Voltage: 3.3V

Brand: AKAI, Model: LTA-15A15M.
Shortly from the TV: LCD, diagonal 15 "(38 cm), there is HDMI, there is USB.
The composition uses MainBoard AS-MST6M181VS-LE1 and an LCD panel (matrix) LTA150XH-L06.
Power Supply Unit (PSU) DC12030011A 12V 3A Power Supply.
AKAI LTA-15A15M TV with LTA150XH-L06 LCD display, 15 "(38 cm) diagonal size in 4: 3 format. 200 cd / m² screen brightness is provided by CCFL (EEFL) fluorescent lamps. Maximum brightness to minimum ratio (contrast) ) is 600: 1. The input high-frequency or video signal can be processed in analog systems PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in standards 480i, 480p, 576i, 576p, 720p. Supported media file formats: MP3, WMA, MPEG4, DivX, MKV, JPEG.
The power of the sound system 6 W (2x3 W) provide two speakers. It uses a NICAM stereo signal processing system and Sound Surround.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV x2, audio x3, component, VGA, HDMI, USB. 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 working in the network mode is 36 watts.
Overall dimensions: With stand 415x342x210 mm, Without stand 415x300x48 mm.
Attention! The LTA150XH-L06 panel of the AKAI LTA-15A15M 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!