Technical description and composition of the DEXP 24A7000 TV, type of panel and applicable modules. The composition of the modules.DEXP LED
Model: 24A7000
Chassis / Version: TP.SIS231.P63
Panel: M240F13-E2-A (G1)
LED backlight: EDGE LED
LED driver (backlight): integrated into MainBoard
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MainBoard: TP.SIS231.P63
IC MainBoard: CPU: SIS231, SPI Flash: 25Q64BSIG, DRAM: W631GG6KB-12
Tuner: NoName
Specifications 24A7000
DEXP 24A7000
General repair guidelines for TV LCD LED
Possible malfunctions
- The DEXP 24A7000 TV does not turn on, does not respond to the remote control and buttons on the control panel, does not light or flash indicators.
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.P63 main board. It is necessary to verify the presence of its output voltages and, if they are completely absent, check the power switches and rectifier diodes for a possible short circuit.
In the event of breakdowns in the secondary circuits of the converter, it can usually fail in short circuit mode, and in the event of a short circuit in the power elements of the primary circuit, the mains fuse or current sensor at the source of the key most often breaks.
Breakdown of power switches (MosFet) in pulsed sources is sometimes caused by malfunctions of other circuit elements, for example, in circuits supplying a PWM controller, frequency-setting or damper ones, as well as in negative feedback (OOS) stabilization circuits. PWM controllers (PWM) PWM SOT23-6, if they do not have visible damage to the case and open short circuit between the terminals, are usually checked by replacement.
- 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 most of these cases, a malfunction is detected in the nodes and backlight elements of the LED panel. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
To check the LED strips, to open all the transitions of the LEDs, several tens of volts or more are needed, it is best to use a current source for such purposes. The breakage of several PN junctions connected in series cannot be detected with a multimeter or tester. In such cases, it is necessary to open the panel and check each LED. If your multimeter cannot open the LED transitions in forward bias, you can sometimes detect the presence of a PN junction of the protective zener diode by connecting the probes in the opposite direction. If the zener diode is broken or broken in short-circuit, then the LED is faulty and needs to be replaced.
- The indicator on the front panel blinks, the TV does not turn on in the operating mode, it does not respond to the remote control.
Repair or diagnostics of the TP.SIS231.P63 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). Complex repair of MB (SSB) is possible only in the conditions of a service center with the necessary equipment. Checking or replacing CPU elements: SIS231, SPI Flash: 25Q64BSIG, DRAM: W631GG6KB-12 requires the necessary training and professional skills to repair modules at the component level. Problems associated with the use of BGA soldering technologies can sometimes be diagnosed by warming up.
If there is no reception of television channels, but the TV is working properly from external devices, first of all it is necessary to check the voltage of the NoName tuner and update the software. The pulses from the I2C bus must be controlled with an oscilloscope.
Owners and users of the DEXP 24A7000 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 24A7000, Main: TP.SIS231.P63, Panel: M240F13-E2-A (G1)
The appearance of MainBoard TP.SIS231.P63 is shown in the figure below:TP.SIS231.P63
Main features of the DEXP 24A7000 device:
Installed matrix (LED-panel) M240F13-E2-A (G1).
A converter is used to power the backlight LEDs, combined with the TP.SIS231.P63 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.P63 module, using CPU chips: SIS231, SPI Flash: 25Q64BSIG, DRAM: W631GG6KB-12 and others.
The NoName tuner provides television reception and channel tuning.
DEXP 24A7000 TV with M240F13-E2-A LCD, 24 "(61 cm) diagonal size of 16: 9 format. The required screen brightness of 300 cd / m² is provided by LED backlighting. Contrast - the ratio of maximum brightness to minimum is 1000: 1. there are TV features that allow you to watch broadcasts and movies in high quality HD with a resolution of 1920x1080 pixels in a graphic decomposition according to the standard 1080p (Full HD). The input high-frequency or video signal is decoded in analog systems PAL, SECAM, NTSC. Graphic processing and generation of color Frova signal is in 480i standards, 480p, 576i, 576p, 720p, 1080i Supported multimedia file formats:. MP3, WMA, MPEG4, DivX, MKV, JPEG.
The power of the sound system 4 W (2x2 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, component, VGA, HDMI x2, 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 standards.
Dimensions: with stand 564x391x139 mm, without stand 564x340x45 mm.
Attention! The M240F13-E2-A (G1) panel of the DEXP 24A7000 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