Technical description and composition of the DEXP 46A7000 TV, type of panel and applicable modules. The composition of the modules.DEXP LED
Model: 46A7000
Chassis / Version: TP.SIS231.PT82
Panel: 46VNBTTSR4LV0.1
T-CON: TT-5120P2VLC2LV0.2
LED driver (backlight): integrated into MainBoard
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MainBoard: TP.SIS231.PT82
IC MainBoard: CPU: SIS231, AUDIO: TPA3110LD2, SPI Flash: 25Q32
Tuner: NoName
Specifications 46A7000
DEXP 46A7000
General repair guidelines for TV LCD LED
Possible malfunctions
- The DEXP 46A7000 does not turn on at all. There is no reaction to the remote control and control buttons from the front panel. Indicator lights do not light or flash.
The malfunction in such cases, first of all, should be sought in the power elements of a switching power supply (IIP) - a network voltage converter (AC / DC), which in this TV model is combined with the MainBoard TP.SIS231.PT82 main board. Then it is necessary to measure its output voltages and, in case of their complete or partial absence, it is necessary to check the serviceability of power switches and rectifier diodes of the converters for a possible 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 power switches, used in switching power supplies, sometimes fail due to a malfunction of any other elements that can put it out of operation in key mode or create an excess of the maximum permissible parameters of the switch. These can be elements supplying the PWM controller, frequency-setting or damping circuits, or negative feedback elements in the stabilization circuit. PWM SOT23-6 PWM controllers, in the absence of visible damage or obvious short-circuit between the terminals, are checked by replacing with new ones, or obviously working.
- 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.
Often in such cases, there is no LED backlight. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
When diagnosing, it is necessary to take into account that it is impossible to check the open in the chain of LED lines without disassembling the panels using a tester or multimeter. To open all PN junctions connected in series, a voltage of the order of several tens of volts is required, and ideally, a current source. By opening the panel, each LED can be checked separately. Typically, Chinese multimeters light up a single 3-volt LED, if you connect probes in the forward direction to it. In dual 6-volt LEDs, the PN junction of its emergency zener diode can serve as an indicator of health. In the event of a LED malfunction, its zener diode will either be cut off or broken into short-circuit.
- The TV does not turn on, does not respond to the remote control. The indicator blinks or signals standby mode.
Repair or diagnostics of the TP.SIS231.PT82 motherboard should begin by checking the stabilizers and power converters needed to power the chips and matrix. If necessary, update or replace the software (software). In cases of attempts to repair the MB (SSB) board, it is necessary to check the health of its elements - CPU: SIS231, AUDIO: TPA3110LD2, SPI Flash: 25Q32 which may require replacement with new ones. If a BGA processor is installed, there is a possibility of a violation of the soldering of the contacts of its conclusions with the board (it is diagnosed by heating).
Before replacing the NoName tuner, if there is no tuning to the channels, you must first check the software and the supply voltage at its terminals. You also need to make sure that the tuner and processor can exchange data via the I2C bus
Owners and users of the DEXP 46A7000 TV should 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 -----------> DEXP 46A7000, Main: TP.SIS231.PT82, Panel: 46VNBTTSR4LV0.1
The appearance of MainBoard TP.SIS231.PT82 is shown in the figure below:
TP.SIS231.PT82
Main features of the DEXP 46A7000 device:
Installed matrix (LED-panel) 46VNBTTSR4LV0.1.
The matrix control uses the Timing Controller (T-CON) TT-5120P2VLC2LV0.2.
To power the backlight LEDs, a converter is used, combined with the TP.SIS231.PT82 main board.
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.
MainBoard - the main board (motherboard) is a TP.SIS231.PT82 module, using CPU chips: SIS231, AUDIO: TPA3110LD2, SPI Flash: 25Q32 and others.
The NoName tuner provides television reception and channel tuning.
DEXP 46A7000 TV with 46VNBTTSR4LV0.1 LCD, 46 "(117 cm) diagonal size in 16: 9 format. The required screen brightness of 350 cd / m² is provided by LED backlighting. Contrast - the ratio of maximum brightness to minimum is 1200: 1. The LCD panel uses direct pixel illumination with rear LEDs - Direct LED.The TV features include viewing programs and movies in high quality HD at a resolution of 1920x1080 pixels in the graphic resolution of the standard 1080p (Full HD). Input high-frequency or video Igna decoded into analog PAL system, SECAM, NTSC Image processing and the formation of the digital signal is in 480i standards, 480p, 576i, 576p, 720p, 1080i, 1080p Supported multimedia file formats:.. MP3, MPEG4, DivX, MKV, JPEG.
The power of the sound system 24 W (2x12 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 x3, 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, 1280x1024, 1360x768, 1920x1080. A digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
Overall dimensions: with stand 1070x697x240 mm, without stand 1070x642x83 mm.
Mass of the TV: 15.3 kg.
Attention! The 46VNBTTSR4LV0.1 panel of the DEXP 46A7000 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.