Sunday, 5 April 2020

REPAIR / SERVICING TV AKAI LTA-15N602M

Technical description and composition of the TV AKAI LTA-15N602M, type of panel and applicable modules. The composition of the modules.
AKAI
Model: LTA-15N602M
Chassis / Version: LS03
Panel: HT150X02-100
Inverter (backlight): SF-200
PWM Inverter: TL-494C
MOSFET Inverter: B3942
Power Supply (PSU): KB5150 CEM-1
MainBoard: JUG7.820.534-2
IC MainBoard: Cpu: MST718BE-LF, Spi Flash: 25X40A, Eeprom: 24LC32, TDA1517P
Tuner: TAF5-C2IP1W 9728BG
Technical Specifications LTA-15N602M
AKAI LTA-15N602M
General recommendations for repairing TV LCD
Possible malfunctions
- The AKAI LTA-15N602M TV does not turn on. There are no signs of operability. The indicators on the front panel do not light or flash, the TV does not respond to the remote control and control buttons.
Failure in such cases should begin to be sought in the 12V power supply circuits. It is necessary to measure its output supply voltages, and in case of their absence, check the serviceability of the power switches of the converters and rectifier diodes for the probability of breakdown in PN semiconductor junctions.
In case of breakdowns in the secondary circuits, the converter, as a rule, can emergency work in the short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse usually breaks.
Breakdown of power switches (MosFet) in pulsed sources is sometimes caused by malfunctions of other circuit elements, for example, in circuits supplying a PWM controller, frequency-setting or damper ones, as well as in negative feedback (OOS) stabilization circuits. PWM controllers (PWM), if they do not have visible damage to the chassis and open short circuit between the terminals, are usually checked by replacement.
- There is no image, there is sound, it is responding to the remote control. Or immediately after turning on for a second, the image may appear and immediately disappear.
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 JUG7.820.534-2 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). Board repair and replacement of Cpu microcircuits: MST718BE-LF, Spi Flash: 25X40A, Eeprom: 24LC32, TDA1517P are carried out with the necessary equipment, and the corresponding element base. Faults associated with the application of BGA processor soldering technologies can be localized by the heating method.
Before replacing the tuner TAF5-C2IP1W 9728BG, if there is no tuning for the channels, you must first check the software and the supply voltage at its terminals. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus
Owners and users of the AKAI LTA-15N602M TV should remember that self-repair without special knowledge, skills and qualifications can be fraught with negative consequences that can lead to complete non-repairability of the device!


FIRMWARE FOR SPI FLASH  ----------->   AKAI LTA-15N602M LS03, Main: JUG7.820.534-2, Panel: HT150X02-100

SCHEMATIC DIAGRAM  / SERVICE MANUAL   ------------------>    AKAI LTA-15N602M Chassis LS03 LTA-15N602M, LTA-15N680HCP, LTA-15N686HCP, LTA-19N508HCP, LTA-22N680HCP, LTA-22N686HCP



 The appearance of the MainBoard JUG7.820.534-2 is shown in the figure below:
JUG7.820.534-2
Key Features of the AKAI LTA-15N602M:
Installed matrix (LCD panel) HT150X02-100.
To power the backlight, an SF-200 inverter is used, it is controlled by a TL-494C PWM controller. As power elements of the inverter, keys of type B3942 are used.
The formation of the necessary supply voltages for all nodes of the AKAI LTA-15N602M TV is carried out by the KB5150 power module, or its analogues.
MainBoard - the main board (motherboard) is a JUG7.820.534-2 module, using Cpu microcircuits: MST718BE-LF, Spi Flash: 25X40A, Eeprom: 24LC32, TDA1517P and others.
The TAF5-C2IP1W 9728BG tuner provides television reception and channel tuning.
Additional technical information about the panel:
Brand: BOE
Model: HT150X02-100
Type: a-Si TFT-LCD, Panel
Diagonal size: 15.0 inch
Resolution: 1024x768, XGA
Display Mode: TN, Normally White, Transmissive
Active Area: 304.128x228.096 mm
Surface: Antiglare (Haze 25%), Hard coating (3H)
Brightness: 250 cd / m²
Contrast Ratio: 500: 1
Display Colors: 16.2M (6-bit + FRC), CIE1931 60%
Response Time: 2/6 (Tr / Td)
Frequency: 60Hz
Lamp Type: 2 pcs CCFL Without Driver
Signal Interface: LVDS (1 ch, 8-bit), 20 pins
Voltage: 3.3V