Wednesday 22 July 2020

REPAIR / SERVICING TV SUPRA STV-LC2644WL

Technical description and composition of the SUPRA STV-LC2644WL TV, panel type and modules used. The composition of the modules.
SUPRA LED
Model: STV-LC2644WL
Chassis / Version: T.MS6M48.7A 10423
Panel: T260XW06 V.4
Power Supply (PSU): LK-OP407501A
MainBoard: T.MS6M48.7A 10423
IC MainBoard: CPU: MST6E48RHS; SPI Flash 25L3206E
Tuner: ET-6T1E-LF-108W-A
STV-LC2644WL Specifications
SUPRA STV-LC2644WL
General recommendations for TV LCD LED repair
Repair of the SUPRA STV-LC2644WL TV should begin with a fault diagnosis, which involves a careful examination of the external and internal elements of the device. From visible external changes in the state of components, it is often possible to determine the further direction of troubleshooting before taking the necessary measurements. Electrolytic capacitors of filters with a swollen case, as well as ring cracks formed in the soldering of the leads of heating elements or a layer of coal on burnt resistors sometimes prompt the repairman about the causes of the malfunction and the possible consequences.
Sometimes the SUPRA STV-LC2644WL TV just won't turn on. No control lamps on the front panel are on or blinking, the TV does not respond to the remote control and does not emit any sounds or any signs of life when turned on. The most probable cause of the malfunction is the failure of the common power supply module LK-OP407501A. If it is working properly, you need to check the processor batteries on the SSB (Main Board). When diagnosing and repairing the power supply, after replacing the swollen capacitors of the secondary rectifier filters (if any), you must first check the mains fuse. If it breaks, the power elements of the transistors and diodes of the rectifier bridge should be checked for avalanche (thermal) breakdown.
As a rule, switches in switching power supplies (SMPS) are quite reliable and rarely fail without reasons that should be looked for by checking other components of the circuit - electrolytic capacitors, resistors and semiconductor elements of the primary circuit. The PWM microcircuit is checked by replacing it with a known good one.
If, when you turn on the TV, the image appears and immediately disappears, or is absent initially when turned on, but there is sound and other functions work, there is a high probability of a malfunction of the LED driver (power converter for the LEDs of the panel backlight T260XW06 V.4). In such cases, the common power module is also subject to verification, in which the electrolytic capacitors of the rectifier filter supplying the LED driver should be checked.
A malfunction in the backlight circuits often occurs due to an open circuit in the power supply circuit of the LED lines. It is required to disassemble the panel and check the LEDs themselves, the ration of their outputs, as well as the reliability of the connections in the connectors and the ration of the connector pins.
An open circuit in the LED lines connected in series can not be detected with a multimeter or tester without disassembling the panel. It takes several tens of volts to open all the junctions, and it is best to use a current source for such purposes.
If the motherboard T.MS6M48.7A 10423 is faulty, first of all it is necessary to check all linear stabilizers or power converters of its chips, and also, if necessary, update the software. Sometimes it is possible to check the health of the MB only by replacing it.
Complex repair of MB (SSB) board is in some cases possible and practiced by repairmen. To do this, check and, if necessary, replace the CPU elements: MST6E48RHS; SPI Flash 25L3206E. Malfunctions in BGA chips are usually easy to detect by warm-up.
If you suspect a malfunction of the ET-6T1E-LF-108W-A tuner, first of all, you need to make sure that there is a supply voltage at the corresponding output of the tuner.
Attention to users! Self-repair of the SUPRA STV-LC2644WL TV without appropriate qualifications and experience can lead to its complete non-repairability!

FIRMWARE FOR SPI FLASH  ----------->   SUPRA STV-LC2644WL, Main: T.MS6M48.7A 10423, Panel: T260XW06 V.4
 The appearance of the MainBoard T.MS6M48.7A is shown in the figure below:
T.MS6M48.7A
T.MS6M48.7A can be used in TVs:
SUPRA STV-LC3244FL (Panel 1080p Full HD 1920x1080), SUPRA STV-LC2625WL (Panel TC260B306), SUPRA STV-LC3225WL (Panel TC315B601), SUPRA STV-LC2644WL (Panel T260XW06 V.4), SUPRA STV-LC4225AFL (Panel TC420F115), SUPRA STV-LC3225LF (Panel V315H4-LE2).
Main features of SUPRA STV-LC2644WL device:
Installed matrix (LED-panel) T260XW06 V.4.
The formation of the necessary supply voltages for all nodes of the SUPRA STV-LC2644WL TV is carried out by the LK-OP407501A power module, or its analogs.
MainBoard - the main board (motherboard) is a T.MS6M48.7A module, using CPU chips: MST6E48RHS; SPI Flash 25L3206E and others.
Tuner ET-6T1E-LF-108W-A provides reception of television programs and tuning to channels.
Additional technical information about the panel:
Brand: AUO
Model: T260XW06 V4
Type: a-Si TFT-LCD, Panel
Diagonal size: 26.0 inch
Resolution: 1366x768, WXGA
Display Mode: AMVA, Normally Black, Transmissive
Active Area: 575.769x323.712 mm
Surface: Antiglare (Haze 2%), Hard coating (3H)
Brightness: 350 cd / m²
Contrast Ratio: 3000: 1
Display Colors: 16.7M (8-bit), CIE1931 68%
Response Time: 6.5 (G to G)
Frequency: 60Hz
Lamp Type: WLED Embedded (LED Driver)
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 12.0V
LED TV SUPRA STV-LC2644WL with LCD T260XW06, diagonal size 26 "(66 cm) 16: 9. The required screen brightness of 400 cd / m² is provided by LED backlighting. Dynamic contrast ratio of 60,000: 1 is achieved by special control of LED operation depending on the illumination of the areas in the scene.This model uses an LED-panel with an edge arrangement of backlighting LEDs - Edge LED.It is possible to view broadcasts and films and images in high quality HD at a resolution of 1366x768 pixels in the standard graphic resolution 720p (HD Ready). high-frequency or video signal is decoded in analog systems PAL, SECAM, NTSC.Graphic processing and digital signal shaping takes place in 480i, 480p, 576i, 576p, 720p, 1080i, 1080p standards.Supported media file formats: MP3, WMA, MPEG4, Xvid, JPEG ...
The power of the speaker system is 18 W (2x9 W), provided by two speakers. The NICAM STEREO audio processing system is used.
External interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV x2, audio x2, component, SCART, RGB, VGA, HDMI x3, USB. A headphone output is provided. To connect a computer or laptop to this TV model, a VGA (D-Sub 15) connector on the TV case is used, this interface supports resolutions: 640x480, 800x600, 1024x768.
The power consumed by the TV in operating mode from the network is 60 watts.
Dimensions: With stand 644x460x165 mm, Without stand 644x414x45 mm.
TV weight: 5.8 kg.
Attention! SUPRA STV-LC2644WL LED TV panel T260XW06 V.4 is an expensive and unreliable element.
Do not allow any impacts on the glass and pressure on the screen surface to avoid damage to the LED panel!
It is also unsafe for liquid to spill onto the screen. Sometimes one drop is enough if it drips down the glass onto the cables to make the TV non-repairable.