Friday 17 July 2020

REPAIR / SERVICING TV SUPRA STV-LC19820WL

Technical description and composition of the TV SUPRA STV-LC19820WL, type of panel and applicable modules. The composition of the modules.
SUPRA LED
Model: STV-LC19820WL
Chassis / Version: V4L10
Panel: LM185WH2
Power Supply (PSU): Adapter 12V
MainBoard: T.VST59.62
IC MainBoard: CPU: TSUMV59XU-Z1, SPI FLASH: GD25Q322, TDA-1517P, TPS54329 (PWM Step-down), BL8024 (PWM Step-down marker GG ..)
Tuner: CDT-3NP5 / 1-10
Control: RC-21b. Login to the service: MENU 1147
Technical Specifications STV-LC19820WL
SUPRA STV-LC19820WL
General repair guidelines for TV LCD LED
Repair of the TV SUPRA STV-LC19820WL should begin with the diagnosis of a malfunction, which involves a careful examination of the external and internal elements of the device. Often, by the external signs and nature of the damage to the elements, it becomes possible to draw some conclusions and determine a further algorithm for finding a defect before making the necessary measurements at control points. In some cases, faulty elements can be seen with the naked eye, for example, carbonized resistors or swollen metal-ceramic capacitors, or electrolytic in rectifier filters. Ring cracks formed in the soldering of the terminals of transformers or heating elements of the circuit are also frequent sources of many malfunctions with a variety of external manifestations.
If the STV-LC19820WL TV does not turn on, does not make any sounds when it is turned on, and also no indicators on the front panel light or blink - there is a high probability of a malfunction in the power module. In some cases, only the stabilizer or power converter of the control processor may be malfunctioning, which is typical for some SUPRA models. Diagnostics and repair of the common power supply should always begin with a check of the mains fuse and the condition of the electrolytic capacitors of the secondary rectifier filters. Defective and swollen capacitors should be replaced with new ones. If the fuse breaks, it is advisable to check for a breakdown, first of all, all the power semiconductor elements of the converter and the diode bridge of the network rectifier, as well as the large electrolytic capacitor of the filter of the network rectifier.
In most cases, key breakdowns in switching power supplies (SMPS) do not occur for no reason and you should look for other faulty circuit elements that could provoke a defect. This can be dried electrolytic capacitors in the primary circuit, and faulty damper elements, as well as dangling resistors or punched semiconductor elements in the stabilization circuits. Possible defective PWM chip from the manufacturer.
If there is no image when you turn on the SUPRA STV-LC19820WL, or it appears for a second and disappears, but there is sound, most likely there is a malfunction in the backlight LED circuit of the LM185WH2 panel, or in their power converter. It is necessary to check the electrolytic capacitors of the filter of secondary rectifiers in the general power supply unit.
In most cases of lack of backlight, there is a need to disassemble the panel in order to check the LEDs, connectors, loops and all contact connections. If one or several LEDs does not work in one line, therefore, they are broken and should be replaced.
To check the LED lines for breaks without disassembling the panel, for example, a current source will help. It is impossible to open series-connected PN junctions with a simple multimeter, a voltage of the order of several tens of volts is required.
On the motherboard T.VST59.62, in case of a malfunction, you should first check the performance of all the stabilizers or power converters of the microcircuits and, if necessary, update the software (software).
Complex repair of MB (SSB) is possible only in the conditions of a service center with the necessary equipment. Checking or replacing CPU elements: TSUMV59XU-Z1, SPI FLASH: GD25Q32 requires the necessary training and professional skills to repair modules at the component level. Problems associated with the use of BGA soldering technologies can be diagnosed by warming up.
If the TV works normally from external devices, but does not tune into television channels, the tuner CDT-3NP5 / 1-10 may be malfunctioning. In such cases, first of all, you should make sure that there are supply voltages at its corresponding terminals, as well as the power supply of varicaps (30-33V).
Owners and users of the SUPRA STV-LC19820WL TV must 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  ----------->   SUPRA STV-LC19820WL (V4L10), Main T.VST59.62, Panel: LM185WH2

 In case of failures in the software of Winbond SPI FLASH microcircuits, they can for some time restore their performance after temperature exposure - heating the soldering station with a hairdryer or even a lighter. Usually this is enough to read the regular contents of the software. In such cases, the chip must be replaced with a new one.
Repair MainBoard
The appearance of MainBoard T.VST59.62 is shown in the figure below:
T.VST59.62
https://1.bp.blogspot.com/-ZHWc4J799xs/XxGtBz_yb_I/AAAAAAABBiI/iwIlpgU6nmIwKvLaZ0kLgMJwI5FqUXmkgCK4BGAYYCw/s1600/T.VST59.62_DCE.jpg
It is advisable to start repairing the T.VST59.62 motherboard based on the TSUMV59Xxx multifunction processor by checking the performance of linear voltage stabilizers or voltage converters necessary to provide power to the processor nodes - 1.2V core power, DDR 1.8V memory and Stand-by 3.3V mode . If there is no image, but the display backlight is working properly, check the power supply voltage of the LCD panel 5V or 12V, depending on the type of panel used.
T.VST59.62 can be used on TVs:
Akai LEA-22V21M (Panel A215ED1DA3-1), ERISSON 22LEN18 (Panel M215HGJ-L21), ERISSON 16LEN18 (Panel N156BGE-L11 Rev.C1), ERISSON 24LEN18 (Panel M236HGE-L20), Fusion FLTV-16L10B (Panel T156LL10-AW4), FUSION FLTV-24T9 (Panel M240HW01 V.B), FUSION FLTV-16T9 (Panel B156XTN02), FUSION FLTV-16T9D (Panel T156LL10-AW4), HYUNDAI H-LED19V13 (Panel CX185LEDM ), SUPRA STV-LC19811FL (Panel M185XTN01.3), SUPRA STV-LC19820WL (Panel LM185WH2), SUPRA STV-LC22820FL (Panel LS215AFTNM), SUPRA STV-LC18250WL (Panel B173HW02 V.1), SUPRA STV-LC22810FL (Panel M215HGE-L21 Rev.C1), SUPRA STV-LC16810WL (Panel B156RW01 V.1), SUPRA STV-LC18251FL (Panel N173HGE-L11 Rev. C1), SUPRA STV-LC22811FL (Panel 1080p Full HD 1920x1080), SUPRA STV-LC1982WL (Panel 1080p Full HD 1920x1080), TELEFUNKEN TF-LED22S3 (Panel M215HGE-P02).
Main features of the SUPRA STV-LC19820WL device:
Installed matrix (LED panel) LM185WH2.
To power all internal nodes of the SUPRA STV-LC19820WL TV, an external adapter 12V type is used.
MainBoard - the main board (motherboard) is a T.VST59.62 module, using CPU chips: TSUMV59XU-Z1, SPI FLASH: GD25Q322, TDA-1517P, TPS54329 (PWM Step-down), BL8024 (PWM Step-down marker GG ..) and others.
The tuner CDT-3NP5 / 1-10 provides reception of television programs and tuning to channels.
Additional technical information about the panel:
Brand: LG Display
Model: LM185WH2-TLE2
Type: a-Si TFT-LCD, Panel
Diagonal size: 18.5 inch
Resolution: 1366x768, WXGA
Display Mode: TN, Normally White, Transmissive
Active Area: 409.8x230.4 mm
Surface: Antiglare, Hard coating (3H)
Brightness: 250 cd / m²
Contrast Ratio: 1000: 1
Display Colors: 16.7M (8-bit)
Response Time: 1.1 / 3.9 (Tr / Td)
Frequency: 60Hz
Lamp Type: 11S2P WLED Without Driver
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 5.0V
LED TV SUPRA STV-LC19820WL with LCD LM185WH2, diagonal size 19 "(48 cm) 16: 9 format. The required brightness of the screen 250 cd / m² is provided by LED backlight LED. Dynamic contrast ratio of 20,000: 1 is achieved by special control of the LEDs depending on the illuminated areas in the plot, this model uses an LED panel with an end-face arrangement of the backlight LEDs - Edge LED. You can watch programs and movies 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 digital signal generation occurs in standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Supported media file formats: MP3, MPEG4, DivX, MKV, JPEG .
The power of the acoustic system of sound 6 W (2x3 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, audio x2, component, SCART, RGB, VGA, USB. 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, 1360x768.
The power consumed by the TV in the operating mode from the network is 36 watts.
Overall dimensions: 525x370x115 mm.
TV Weight: 5.1 kg.
Attention! The LM185WH2 panel of a SUPRA STV-LC19820WL LED TV is an expensive and unreliable element.
Avoid any impact on the glass and pressure on the surface of the screen to avoid damage to the LED panel!
It is also unsafe to get liquid on the screen. Sometimes one drop is enough if it flows down the glass onto the cables so that the TV becomes unrepairable.