Technical description and composition of the SUPRA STV-LC40T840WL TV, panel type and modules used. The composition of the modules.SUPRA LED
Model: STV-LC40T840WL
Chassis / Version: V1L12
Panel: C390X14-E4-A
LED driver (backlight): integrated into MainBoard
PWM LED driver: MP4012
MOSFET LED driver: MMD14N25
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MOSFET Power: TO-220
MainBoard: JUC7.820.00123957
IC MainBoard: CPU: 9206B 1533-DBN MSMSKY, SPI Flash: 25Q64CSIG, AUDIO: TPA3110D
Tuner: DM121 C816RH
STV-LC40T840WL Specifications
SUPRA STV-LC40T840WL
General recommendations for TV LCD LED repair
Possible malfunctions
- TV SUPRA STV-LC40T840WL does not turn on and does not show any signs of operation at all. No response to the remote control and front panel control buttons.
In this case, the main Switching Power Supply, the AC / DC mains voltage converter, whose elements are located on the MainBoard JUC7.820.00123957 main board, may be faulty. It is then necessary to measure its output voltages and, if they are absent, the power switches (TO-220) and rectifier diodes of the converters should be checked for the probability of a short circuit.
In case of breakdowns of semiconductors in the secondary circuits of any converter, as a rule, it can operate in an emergency mode of short circuit without output voltages, and with a short circuit in the elements of the primary circuit, the mains fuse most often breaks off immediately and less often the current sensor in the source of the key.
Breakdown of Mos-Fet switches used in switching power supplies is often caused by malfunctions of other elements, for example, in the power supply circuit of a PWM regulator, in frequency-setting or damper circuits, as well as in negative feedback stabilization. PWM microcircuits (PWM) PWM SOT23-6 are usually checked by replacing them with new ones, or knowingly working.
- There is no image, there is sound, it reacts to the remote control. Or the image may appear for a second when turned on and disappear immediately.
The malfunction in most of these cases is found in the nodes and elements of the LED panel backlighting. Most often the reason for this is a break in the LEDs, or poor contact in the connectors of the brackets, less often the LED driver may be faulty.
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 JUC7.820.00123957 motherboard should begin with checking the stabilizers and power converters necessary to power the microcircuits and matrix. If necessary, you should update or replace the software (software). When repairing an MB board, you need to check its components CPU: 9206B 1533-DBN MSMSKY, SPI Flash: 25Q64CSIG, AUDIO: TPA3110D. Defective elements must be replaced. If chips with BGA soldering technology are used, the problem in its implementation is detected by local heating of the chip.
If the TV operates normally from external devices, but does not tune to TV channels, the DM121 C816RH tuner may be faulty. In such cases, first of all, you should make sure that the supply voltage is present at its corresponding terminals. It is also necessary to make sure that the data exchange between the tuner and the processor is possible via the I2C bus. Sometimes the reason for the inoperability of the tuner may be a software failure.
We remind users again! Attempts to self-repair the SUPRA STV-LC40T840WL TV without the appropriate qualifications and the necessary experience can lead to its complete non-repairability!
DOWNLOAD FIRMWARE FOR SPI FLASH -----------> SUPRA STV-LC40T840WL V1L12, Main: JUC7.820.00123957, Panel: C390X14-E4-A
The appearance of the MainBoard JUC7.820.00123957 is shown in the figure below:JUC7.820.00123957
JUC7.820.00123957 can be used in TVs:
DEXP F40B7200C (Panel C400F14-E6-C (G5)), SUPRA STV-LC40T440FL (Panel C400F15-E2-S (G01)), SUPRA STV-LC40T800FL (Panel C400F14-E8-C).
Main features of SUPRA STV-LC40T840WL device:
Installed matrix (LED-panel) C390X14-E4-A.
To power the backlight LEDs, a converter combined with the JUC7.820.00123957 main board is used, controlled by the MP4012 PWM controller. The keys of the MMD14N25 type are used as power elements of the LED driver.
The power module is combined with the MainBoard and is made according to the AC / DC flyback voltage converter using SOT23-6 PWM microcircuits and TO-220 type power switches.
MainBoard - the main board (motherboard) is a JUC7.820.00123957 module using CPU chips: 9206B 1533-DBN MSMSKY, SPI Flash: 25Q64CSIG, AUDIO: TPA3110D and others.
Tuner DM121 C816RH provides reception of television programs and tuning to channels.
SUPRA LED TV STV-LC40T840WL with LCD C390X14-E4-A, diagonal 39 "(99 cm) in 16: 9 format. The required screen brightness of 300 cd / m² is provided by LED backlighting. Dynamic contrast ratio of 100,000: 1 is achieved special control of the LEDs depending on the illumination of areas in the scene. The display technology of the model uses LED LED backlight. 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 digital signal shaping takes place in 480i, 480p, 576i, 576p, 720p, 1080i, 1080p standards Supported media file formats: MP3, WMA, MPEG4, MKV, JPEG.
Speaker power of 16 W (2x8 W) is 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, audio x2, component, VGA, HDMI x3, USB. 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 standards.
Overall dimensions: 990x635x138 mm.
Attention! Panel C390X14-E4-A of SUPRA STV-LC40T840WL LED TV 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.