Saturday, 18 July 2020

REPAIR / SERVICING TV SUPRA STV-LC1977WLD

Technical description and composition of the TV SUPRA STV-LC1977WLD, type of panel and applicable modules. The composition of the modules.
SUPRA LED
Model: STV-LC1977WLD
Chassis / Version: V5L09
Panel: M185BGE-P02 // HE185WX1-100
LED driver (backlight): HK230M4CH
PWM LED driver: MP3398A
Power Supply (PSU): Adapter 12V
MainBoard: CV181L-Y
IC MainBoard: FLASH: EN25Q32, DVD: MPEG BOARD-GM-CH1089J-V1.2, FLASH: MX25L1605, Optics: SF-HD850
Tuner: CDT-3SP512-37
Control: Service Login: SOURCE 2580
Technical Specifications STV-LC1977WLD
SUPRA STV-LC1977WLD
General repair guidelines for TV LCD LED
Repair and diagnostics of any electronic device, in particular SUPRA STV-LC1977WLD, it is advisable to begin with a careful external examination of the internal and external elements. Many visible changes in the state of elements make it possible to determine the further direction of troubleshooting and localization of the defect. Charred paint on the upper layer of resistors, electrolytic capacitors of rectifier filters swollen after boiling, cracked soldering on the leads of heating elements or transformers can often suggest the causes of the defect and possible consequences.
In the case when the STV-LC1977WLD does not turn on, does not respond to the remote control and front panel buttons, does not blink lights and does not show any signs of operability, the power module is probably faulty in this case. If it is serviceable with such manifestations, it is necessary to check the power supply stabilizer (converter) of the processor on the motherboard. If there are no swollen filter capacitors of the secondary rectifiers, the diagnostics of the power supply should be started by checking the fuse and, if it is broken, first of all, check all power semiconductor elements primary circuit - diodes and transistors for the probability of an avalanche or thermal breakdown.
As a rule, the keys in switching power supplies (SMPS) are reliable enough and rarely fail for no reason to be looked for by checking other components of the circuit - electrolytic capacitors, resistors and semiconductor elements of the primary circuit. The PWM chip is checked by replacing it with a known good one.
If, when turning 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 (the power converter for the backlight LEDs of the M185BGE-P02 panel). In such cases, the general 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 a break in the power supply lines of the LED lines. It requires disassembling the panel and checking the LEDs themselves, the rations of their terminals, as well as the reliability of the connections in the connectors and rations of the terminals.
It is impossible to check the LED bars for a break without disassembling the panel with a multimeter or tester. For these purposes, it is necessary to open all series-connected PN junctions and a voltage of the order of tens of volts will be required, and ideally a current source.
In cases of attempts to repair the CV181L-Y motherboard, it is necessary to check the performance of the stabilizers or power converters of its microcircuits and, if possible, update the software (software). BGA chips can in most cases be diagnosed by local heating.
In some cases, to repair the MB (SSB) board, it may be necessary to replace chips - FLASH: EN25Q32, DVD: MPEG BOARD-GM-CH1089J-V1.2, FLASH: MX25L1605, optics: SF-HD850 with new or known working ones. In cases where BGA technologies are used, defects are usually localized by the heating method.
If you suspect a malfunction of the tuner CDT-3SP512-37, first of all, you need to make sure that the voltage of the varicaps (30-33V) is on the corresponding output of the tuner, as well as other voltage supplying it.
Remember! Attempts to self-repair the SUPRA STV-LC1977WLD TV by users without appropriate qualifications and the necessary experience can lead to serious negative consequences!

FIRMWARE FOR SPI FLASH  ----------->   SUPRA STV-LC1977WLD(V5L09) MAIN CV181L-Y, PANEL: M185BGE-P02

FIRMWARE FOR SPI FLASH  ----------->   SUPRA STV-LC1977WLD(V6L10), MAIN CV181L-Y


FIRMWARE FOR SPI FLASH  ----------->   SUPRA STV-LC1977WLD(V3K12)



SUPRA STV-LC1977WLD (V3K12) - MAIN: CV181L-A, SPI FLASH: W25Q32, TUNER: AFT7 / W110G, PANEL: CLAB185WA04-V4.
STV-LC1977WL - Version V6L11, Main Board: T.VST29.61C 12296, CPU-TSUMV59XU-Z1, SPI FLASH-25Q32BSIG.

In the event of a failure in the software of the SPI FLASH chip from Winbond, we recommend that you replace it with a new one. Sometimes faulty SPI Winbond microcircuits can be temporarily restored after the soldering station warms up with a hairdryer. This is usually enough to read its contents.


To reduce the backlight current, you should proportionally increase the total resistance of the resistors relative to the case at the ISET pin of the MP3398A controller. ISET (Current Setting) - Pin 8 in SOIC-20 package or Pin 6 in SOIC-16 package.
Repair MainBoard
The appearance of the MainBoard CV181L-Y is shown in the figure below:
The CV181L-Y motherboard uses the MST6M181VG processor, combined with a scaler and installed using the BGA technology.
It is advisable to start repairing this MainBoard with checking the linear stabilizers and voltage converters required to provide power to the processor units: 1.2V, 2.5V, 3.3V. If there is no image, but the display backlight is working properly, it is necessary to check the power of the 5V or 12V LCD panel, depending on the type of panel used, which should be measured directly on the LVDS connector. If the TV does not exit Stand-by mode and does not respond to the remote control and control buttons, if the necessary supply voltages are available, update the SPI Flash software.
CV181L-Y can be used in TVs:
FUSION FLTV-19L16B (Panel M185B3-PA1), SUPRA STV-LC1977WLD (Panel M185BGE-P02), SUPRA STV-LC2477FLD (Panel HK236WLEDM-IH61H), THOMSON T22E32HU (Panel LM215WF4 (TL)(E7)).
The appearance of the power supply
Main features of SUPRA STV-LC1977WLD device:
Installed matrix (LED-panel) M185BGE-P02 or HE185WX1-100.
To power the backlight LEDs, the HK230M4CH LED driver is used, controlled by the MP3398A PWM controller.
To power all internal components of the SUPRA STV-LC1977WLD TV, an external adapter 12V is used.
MainBoard - the main board (motherboard) is a CV181L-Y module, using FLASH: EN25Q32 chips, DVD: MPEG BOARD-GM-CH1089J-V1.2, FLASH: MX25L1605, optics: SF-HD850 and others.
The CDT-3SP512-37 tuner provides reception of television programs and tuning to channels.
Additional technical information about the panel:
Brand: CHIMEI INNOLUX
Model: M185BGE-P02
Type: a-Si TFT-LCD, CELL
Diagonal size: 18.5 inch
Resolution: 1366x768, WXGA
Display Mode: TN, Normally White, Transmissive
Active Area: 409.8x230.4 mm
Surface: Antiglare (Haze 25%), Hard coating (3H)
Glass Depth: 0.50 + 0.50 mm
Transmissivity: 6.6% (with Polarizer)
Contrast Ratio: 1000: 1
Display Colors: 16.7M (8-bit)
Response Time: 1.5 / 3.5 (Tr / Td)
Frequency: 60Hz
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 5.0V
LED TV SUPRA STV-LC1977WLD with LCD M185BGE-P02, diagonal 19 "(48 cm) 16: 9. The required screen brightness of 250 cd / m² is provided by LED backlighting. Contrast - the ratio of maximum brightness to minimum is 700: 1 Dynamic contrast ratio of 14000: 1 is achieved by special control of the LEDs depending on the illumination of areas in the scene.This model uses an LED panel with an edge LED backlighting - Edge LED. It is possible to view broadcasts and films and images in high quality HD at resolution 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 standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Supported media file formats: MP3, WMA, MPEG4, DivX, VideoCD, SVCD, Picture CD, 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, VGA, HDMI, 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 operating mode from the network is 45 watts.
Overall dimensions: 464x346x186 mm.
TV weight: 3.6 kg.
Attention! SUPRA STV-LC1977WLD LED TV panel M185BGE-P02 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 plumes, so that the TV l is not repairable