Technical description and composition of the SUPRA STV-LC1505W TV, panel type and modules used. The composition of the modules.SUPRA
Model: STV-LC1505W
Chassis / Version: V1I10
Panel: HT156WX1-100
MainBoard: B.HVB21D 9022
IC MainBoard: SPI FLASH KH25L4005, SOUND: TDA1517
Tuner: ET-6T1E-LF-108W-A
STV-LC1505W Specifications
SUPRA STV-LC1505W
General recommendations for TV LCD repair
It is advisable to start repairing all electronic devices, including the SUPRA TV based on the V1I10 chassis, with an external examination of its external and internal elements. Based on visible changes in the state of components, it is usually possible to determine the further direction of troubleshooting and localization of the defect before taking the necessary measurements. In some cases, defective elements can be seen with the naked eye, for example, charred resistors or swollen sintered capacitors, or electrolytic ones in rectifier filters. The formed ring cracks in the soldering of the terminals of transformers or heating circuit elements are also frequent sources of many malfunctions with a variety of external manifestations.
If SUPRA STV-LC1505W does not turn on, none of the indicator lamps on the front panel will light up or blink, therefore, there is a very high probability of a power module malfunction. In some cases, only the processor power regulator may be faulty. When diagnosing and repairing the power supply, first of all, you should replace the swollen capacitors of the secondary rectifier filter and check the fuse and, if it is broken, you must identify the cause. Often in such cases an avalanche (thermal) breakdown is detected in the power semiconductor elements of the module - rectifier diodes and transistors in the primary circuit.
The reasons for the breakdown of the power switch in switching power supplies (SMPS) can be different, for example, a malfunction of semiconductor elements or electrolytic capacitors in the stabilization circuits of the primary circuit, as well as a failure in the operation of a PWM regulator microcircuit or breaks in resistors in its strapping.
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 inverter (backlight power converter). In such cases, the lamps, the inverter and the common power module must be checked, in which the electrolytic capacitors of the rectifier filter supplying the inverter must be checked. When disabling the protection of the inverter (to enable diagnostics), special care must be taken due to the risk of failure of the power elements. After the completion of all repair work, it is imperative to restore the protection circuits for the full and safe further operation of the TV by the user.
The SUPRA STV-LC1505W has no picture when a signal is present, often caused by a malfunctioning display backlight. Moreover, the problem can be both inside the LCD panel (matrix) HT156WX1-100, for example, a malfunction of CCFL (EEFL) lamps, and outside in their power source - an inverter.
Without backlighting, sometimes you can see a barely noticeable image with a certain successful hit of external light on the screen.
Often, to repair the backlight, disassembly of the HT156WX1-100 LCD panel is required - a painstaking process that requires special attention and accuracy from the master. In such cases, there is a possibility, with the slightest negligence, to damage the glass or loops and the TV may become unrepairable.
We strongly do not recommend doing such work to owners of TVs and craftsmen who do not have experience in repairing LCD panels! Moreover, at home (at the owner's home).
If there is no image in the presence of backlight, the screen becomes slightly lighter when turned on, and if the TV is open, the light from the lamps can be seen through the holes in the panel case.
In this case, there may be a malfunction inside the panel, damage to strips, loops, the T-CON board (Timing Controller) may be defective. But often the main board MainBoard B.HVB21D also turns out to be faulty, a software failure is also possible.
In such cases, the master first of all needs to check the main supply voltage of the panel at the LVDS connector, the fuses on the T-CON board or the panel brackets, as well as the supply and reference voltages for the line and column drivers - VGH, VGL, Vcom.
If all the above measurements are within the normal range, then the oscilloscope should track the passage of LVDS signals from MainBoard B.HVB21D, as well as synchronizing signals from T-CON to loops with drivers.
Diagnostics and repair of the B.HVB21D 9022 motherboard is carried out by checking the functionality of the stabilizers or power converters of the module chips. In some cases, a software update is required. Complicated MB (SSB) repair is possible only in the conditions of a service center with the necessary equipment. Checking or replacing SPI FLASH KH25L4005, SOUND: TDA1517 elements requires the necessary training and professional skills to repair modules at the component level. Problems associated with BGA soldering technologies can be diagnosed by the warm-up method.
Attention to users! Self-repair of the SUPRA STV-LC1505W TV without proper qualifications and experience can lead to its complete non-repairability!
DOWNLOAD FIRMWARE FOR SPI FLASH -----------> SUPRA STV-LC1505W V1I10, MAIN B.HVB21D, PANEL HT156WX1-100
The appearance of MainBoard B.HVB21D is shown in the figure below:B.HVB21D
Main features of SUPRA STV-LC1505W device:
Installed matrix (LCD panel) HT156WX1-100.
The necessary supply voltages for all nodes of the SUPRA STV-LC1505W TV are provided by a switching power supply.
MainBoard - the main board (motherboard) is a B.HVB21D module, using SPI FLASH KH25L4005, SOUND: TDA1517 and others.
Tuner ET-6T1E-LF-108W-A provides reception of television programs and tuning to channels.
LCD TV SUPRA STV-LC1505W with LCD HT156WX1-100, 15 "diagonal, 16: 9 format. Screen brightness of 250 cd / m² is provided by CCFL (EEFL) fluorescent lamps. Contrast - ratio of maximum brightness to minimum is 500 : 1. It is possible to view broadcasts and films and images in high quality HD at a resolution of 1366x768 pixels in the standard of graphic decomposition 720p (HD Ready). Input high-frequency or video signal is decoded in analog systems PAL, SECAM, NTSC. Graphic processing and formation of a digital signal occurs in 480i, 480p, 576i, 576p, 720p, 1080i standards Stereo sound is realized by two built-in speakers The 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, S-Video, VGA. 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.
Dimensions: With stand 1125x812x204 mm, Without stand 1054x791x120 mm.
TV weight: 3.9 kg.
Attention! SUPRA STV-LC1505W LCD TV panel HT156WX1-100 is its most expensive component.
Avoid hitting the glass and putting pressure on the screen surface to avoid irreversible damage to the LCD panel! Once again, I remind users and TV owners.
Self-repair attempts can have serious negative consequences, up to complete non-repairability.
