Technical description and composition of the DAEWOO L32S790VNE TV, panel type and applicable modules. The composition of the modules.DAEWOO LED
Model: L32S790VNE
Chassis / Version: 35022477
Panel: LC320DXY (SJ) (A8)
LED backlight: 32660 35022269
LED driver (backlight): integrated into MainBoard
PWM LED driver: SOP-16
MOSFET LED driver: TO-252
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MOSFET Power: TO-252
MainBoard: 35022477 REV-02
IC MainBoard: SPI FLASH: W25Q16V
Tuner: CDT-9NT372
Technical Specifications L32S790VNE
DAEWOO L32S790VNE
General repair guidelines for TV LCD LED
Possible manifestations of defects
- The DAEWOO L32S790VNE TV does not turn on and does not show any signs of turning on, it does not respond to the control buttons or the remote control.
The malfunction in such cases, first of all, should be sought in the power elements of a pulsed power supply (IIP) - a network voltage converter (AC / DC), which in this TV model is combined with the MainBoard 35022477 main board. Then we recommend measuring its output voltage and, in case their absence, it is necessary to check the serviceability of power switches (TO-252) and rectifier diodes of converters for probable short circuit.
In case of breakdowns of diodes in the secondary circuits, the converter can operate in emergency short circuit mode without output voltages, and during short circuit in the power elements of the primary circuit, the mains fuse and / or current sensor at the source of the key usually breaks.
Mos-Fet keys used in switching power supplies usually fail due to a malfunction of other elements that can put it out of operation in key mode or provoke an excess of the maximum current or voltage. These can be circuits supplying the PWM controller, damping or frequency-setting circuits, or elements of OOS (negative feedback) in the stabilization circuit. PWM controllers (PWM) PWM SOT23-6, in the absence of external damage and short circuit between the terminals, are checked by replacing with obviously good ones.
- There is no image, there is sound, it responds to the remote control. Or the image may appear for a second when turned on and immediately disappears.
In such cases, the most likely malfunction of the LED backlight elements. The reason can sometimes be in the power of the LEDs, but more often in their malfunction (breakdown or break), sometimes in the violation of the contact connections of the LED strips.
To detect a break in the LED lines without disassembling the panel, a current source is required. It is impossible to open transitions connected in series with a simple multimeter; voltage of several tens of volts is necessary.
- The TV does not enter the operating mode, does not respond to the remote control. The indicator on the front panel lights constantly or blinks.
Repair or diagnostics of the 35022477 motherboard should begin by checking the stabilizers and power converters needed to power the microcircuit and matrix. If necessary, update or replace the software (software). In cases of complex repairs of MB (SSB) and in the presence of the necessary skills and equipment, sometimes it may be necessary to replace its SPI FLASH chips: W25Q16V and other possible faulty components. Malfunctions associated with the application of BGA soldering technologies are usually easily diagnosed by the heating method.
If you suspect a malfunction of the CDT-9NT372 tuner, first of all, you need to verify the correctness of the software, as well as the presence of the required voltage levels and the data exchange pulses with the processor via the I2C bus at the corresponding tuner pins.
Attention! For users and owners of L32S790VNE TVs who do not have the appropriate qualifications, knowledge and experience, we categorically do not recommend attempting self-repair in order to avoid negative consequences that could lead to complete non-repairability of the device.
FIRMWARE FOR SPI FLASH -----------> DAEWOO L32S790VNE, Main: 35022477 REV-02, Panel: LC320DXY (SJ)(A8)
The appearance of the MainBoard 35022477 is shown in the figure below:35022477
Main features of the DAEWOO L32S790VNE device:
Installed matrix (LED-panel) LC320DXY (SJ) (A8).
To power the backlight LEDs, a converter is used, combined with the main board 35022477, controlled by the SOP-16 PWM controller. As power elements of the LED driver, keys of the TO-252 type are used.
The power module is combined with the MainBoard and is made according to the flyback AC / DC voltage converter circuit using PWM SOT23-6 microcircuits and TO-252 type power switches.
MainBoard - the main board (motherboard) is a module 35022477, using microchips SPI FLASH: W25Q16V and others.
Tuner CDT-9NT372 provides the reception of television programs and tuning to channels.
Additional technical information about the panel:
Brand: LG Display
Model: LC320DXY-SJA8
Type: a-Si TFT-LCD, CELL
Diagonal size: 31.5 inch
Resolution: 1366x768, WXGA
Display Mode: IPS, Normally Black, Transmissive
Active Area: 697.685x392.256 mm
Surface: Antiglare (Haze 3%), Hard coating (2H)
Transmissivity: 6.45% (with Polarizer)
Contrast Ratio: 1200: 1
Display Colors: 16.7M (8-bit)
Response Time: 8/10 (Tr / Td)
Frequency: 60Hz
Signal Interface: LVDS (1 ch, 8-bit), 30 pins
Voltage: 12.0V
Brand: DAEWOO, Model: L32S790VNE.
Briefly from the TV: LCD, LED backlight, 32 ", 1366x768, 720p HD, DVR, sound: 16W, HDMI: 3, Internet access, Wi-Fi, Smart TV.
The composition uses MainBoard 35022477 REV-02 and LCD-panel LC320DXY (SJ) (A8). The power supply is combined with the MainBoard.
Technical description
DAEWOO L32S790VNE LED TV with LC320DXY LCD, 32 "(81 cm) diagonal size in 16: 9 format. The required screen brightness of 240 cd / m² is provided by LED backlighting. LED display technology is implemented in the model’s display technology. Viewing is possible images in high quality HD at a resolution of 1366x768 pixels in the standard of graphic decomposition 720p (HD Ready) TV Model L32S790VNE has built-in SMART software and the installed Android Operating System.
Connecting to a network can be done via Wi-Fi.
Supported media file formats: MP3, MPEG4, HEVC (H.265), Xvid, MKV, JPEG.
The power of the sound speaker system 16 W (2x8 W) is provided by two speakers. It uses a NICAM stereo signal processing system and Sound Surround.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, component, VGA, HDMI x3, MHL, USB x2, Ethernet (RJ-45), Wi-Fi, Miracast. An output for connecting headphones is provided. A digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
Overall dimensions: With stand 731x481x216 mm, Without stand 731x435x85 mm.
Attention! The LC320DXY (SJ) (A8) panel of a DAEWOO L32S790VNE 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.
