Friday, 31 July 2020

REPAIRING / SERVICING TV SUPRA STV-LC32ST670WL

Technical description and composition of the SUPRA STV-LC32ST670WL TV, panel type and modules used. The composition of the modules.
SUPRA LED
Model: STV-LC32ST670WL
Chassis / Version: V1N10
Panel: ST3151A05-5 SEL320HY (CD0-701)
LED backlight: SEL320HY-CD0300-X3
T-CON: MT3151A05-5-XC-5
LED driver (backlight): integrated into PSU
PWM LED driver: MP3398
MOSFET LED driver: ME15N10-G
Power Supply (PSU): 168P-L2L021-W0 5800-L2L021-W000 P4839B
PWM Power: TEA1733
MOSFET Power: TF11N70
MainBoard: 5800-A6M88G-0P10 VER00: 00
IC MainBoard: 24C64, TPA3110D2
Control: IR: 5800-RNE510-RP00, WiFi: 5800-W81920-0P50
STV-LC32ST670WL Specifications
SUPRA STV-LC32ST670WL
General recommendations for TV LCD LED repair
Possible manifestations of defects
- SUPRA STV-LC32ST670WL does not turn on, indicators on the front panel are not lit or blinking. The TV does not respond to control buttons and the remote control.
In some of these cases, a fault is detected in the 168P-L2L021-W0 power supply module. It is necessary to measure its output supply voltages, and in their absence, check the serviceability of the power switches (TF11N70) of the converters and rectifier diodes for the probability of breakdown in semiconductor PN junctions.
In the event of diode breakdowns in the secondary circuits, the converter can operate in an emergency mode of short circuit without output voltages, and with a short circuit in the power elements of the primary circuit, the mains fuse and / or current sensor in the source of the key usually breaks off.
Mos-Fet keys used in switching power supplies usually fail due to a malfunction of other elements, which can disable it in key mode, or provoke an excess of the maximum current or voltage values. These can be circuits supplying the PWM controller, damper or frequency setting circuits, or OOS (negative feedback) elements in the stabilization circuit. PWM controllers (PWM) TEA1733, in the absence of external damage and a short circuit between the terminals, are checked by replacing them with a known good one.
- There is no picture, but there is sound, it reacts to the remote control. Or the image appears when turned on and disappears immediately
In such cases, the most likely malfunction of the LED panel backlighting elements. The reason may be both in the power supply of the LEDs, in their serviceability (breakdown or breakage), as well as in the violation of the contact connections of the LED strips.
Without a special current source, it is impossible to check the line of LEDs connected in series, and it is unsafe for them to use any voltage sources above 12V for this purpose. Then all that remains is to open the panel and check each LED separately. Typically, Chinese multimeters with a 9V power supply lightly light up one 3-volt LED, if you connect the probes to it in the forward direction, the red probe to the anode, and the black one to the cathode. For dual 6-volt LEDs, the PN junction of its emergency zener diode can serve as an indicator of LED health. In the event of a malfunction of the LED, its zener diode will either be cut off or broken into the K / Z.
- The TV does not go into operation, does not respond to the remote control. The indicator on the front panel is on or blinking.
Repair or diagnostics of the 5800-A6M88G-0P10 motherboard should begin with checking the stabilizers and power converters required to power the microcircuits and matrix. If necessary, you should update or replace the software (software). Often the MB (SSB) board needs to be replaced in case of complex malfunctions that are difficult to detect. When trying to repair, you should check its elements - 24C64, TPA3110D2 and replace the failed chips with new ones. Some malfunctions may be associated with the use of BGA soldering technologies in modern Main Board. Typically, such defects are detected by local heating of the chip.
Users and owners of TVs should remember that attempts to self-repair the SUPRA STV-LC32ST670WL TV without the appropriate qualifications and the necessary experience can lead to serious negative consequences!


 The appearance of the MainBoard 5800-A6M88G-0P10 is shown in the figure below:
5800-A6M88G-0P10
External view of the power supply
Main features of SUPRA STV-LC32ST670WL device:
Installed matrix (LED panel) ST3151A05-5 SEL320HY (CD0-701).
Matrix control uses Timing Controller (T-CON) MT3151A05-5-XC-5.
A converter combined with a power supply is used to power the backlight LEDs, and is controlled by the MP3398 PWM controller. The keys of the ME15N10-G type are used as power elements of the LED driver.
The formation of the necessary supply voltages for all nodes of the SUPRA STV-LC32ST670WL TV is carried out by the 168P-L2L021-W0 power module, or its analogs using TEA1733 microcircuits and TF11N70 power switches.
MainBoard - the main board (motherboard) is a 5800-A6M88G-0P10 module, using 24C64, TPA3110D2 and others.
LED TV SUPRA STV-LC32ST670WL with LCD ST3151A05-5, diagonal size 32 "(81 cm) 16: 9. The required screen brightness of 300 cd / m2 is provided by LED backlight. Dynamic contrast ratio of 80000: 1 is achieved by special control operation of LEDs depending on the illumination of areas in the scene.The technology of manufacturing the display model uses LED LED backlighting.It is possible to view programs and films and images in high quality HD at a resolution of 1366x768 pixels in the standard of graphic decomposition 720p (HD Ready).
STV-LC32ST670WL TV is equipped with SMART software, built-in applications and the ability to work on the Internet. Internet connection can be made via Wi-Fi wireless connection. The input high-frequency or video signal is decoded in analog systems PAL, SECAM, NTSC. Graphic processing and digital signal shaping takes place in the 480i, 480p, 576i, 576p, 720p, 1080i, 1080p standards. Supported media file formats: MP3, WMA, MPEG4, MKV, JPEG.
Speaker power 12 W (2x6 W) is provided by two speakers. The NICAM STEREO audio processing system is used.
An external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), audio x2, VGA, HDMI x3, MHL, USB x2, Ethernet (RJ-45), Wi-Fi. A headphone output is provided. To connect a computer or laptop to this TV model, use the VGA (D-Sub 15) connector on the TV case, this interface supports resolutions: 640x480, 800x600, 1024x768, 1360x768. The digital tuner is capable of receiving TV channels in the DVB-T MPEG4, DVB-C, DVB-T2, DVB-S2 standards.
Overall dimensions: 818x508x128 mm.
Attention! Panel ST3151A05-5 SEL320HY (CD0-701) SUPRA LED TV STV-LC32ST670WL 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.