Saturday 11 April 2020

REPAIR / SERVICING TV DEXP 16A3000

Technical description and composition of the DEXP 16A3000 TV, type of panel and applicable modules. The composition of the modules.
DEXP LED
Model: 16A3000
Chassis / Version: CVMV29L-F
Panel: N156BGE-L2 1366x768 WXGA
LED backlight: EDGE LED
LED driver (backlight): integrated into T-CON
Power Supply (PSU): Adapter 12V
MainBoard: CVMV29L-F
IC MainBoard: CPU: TSUMV59XU-Z1, SPI Flash - 25Q32FVSIG, AUDIO: NS4263
Tuner: CDT-3NP5I1-10
Specifications 16A3000
DEXP 16A3000
General repair guidelines for TV LCD LED
Possible malfunctions
- The DEXP 16A3000 TV does not turn on, does not respond to the remote control and the control panel buttons, the indicators do not light or flash.
In such cases, the adapter power supply is usually faulty.
The external adapter 12V power supply is not always subject to repair, especially since the owner can purchase it independently. But, in some cases, it makes sense to open it and eliminate the simple typical defects inherent in converters in pulsed sources. It is necessary to measure its output supply voltages, and in case of their absence, check the serviceability of the power switches of the converters and rectifier diodes for the probability of breakdown in PN semiconductor junctions.
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. IC_Power PWM controllers, in the absence of visible damage or open faults between the terminals, are checked by replacing them with new ones, or obviously working ones.
- There is no image, there is sound, it is responding to the remote control. Or immediately after turning on for a second, the image may appear and immediately disappear.
In some of these cases, the malfunction is caused by a lack of backlighting on the display. The reason can 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.
It is impossible to detect a break in the LED line without disassembling the panel with a simple multimeter. The LEDs are connected in series and to open their transitions, a voltage of several tens of volts is required. Ideally, a current source is suitable for such purposes. You can open the panel and check each LED separately. Typically, Chinese multimeters light up a single 3-volt LED, if you connect the probes in the forward direction to it (red probe to the anode, black to the cathode). 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 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 CVMV29L-F 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: TSUMV59XU-Z1, SPI Flash - 25Q32FVSIG 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).
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 tuner tuner and update the software. The pulses from the I2C bus must be controlled with an oscilloscope.
Once again, we remind TV users: you should not make attempts to repair it yourself without the appropriate knowledge, experience and the necessary qualifications! Entrust repair to professionals with sufficient experience in the field of repair of electronic equipment.


FIRMWARE FOR SPI FLASH  ----------->   DEXP 16A3000, Main: CVMV29L-F, Panel: N156BGE-L2 1366x768 WXGA


 The appearance of the MainBoard CVMV29L-F is shown in the figure below:
CVMV29L-F
CVMV29L-F can be used in TVs:
DEXP H24C3000E (Panel CX236DLEDM), DEXP H16B3000ED (Panel N156BGE-L21), DEXP F22B3000E (Panel T215HVN01.1 CX215LEDM), DEXP 16A3000 (Panel N156BGE-L2 1366x768 WXGA ), DEXP 19A3000 (Panel CX185LEDM), DEXP 22A7000 (Panel CX215LEDM), MYSTERY MTV-1628LW (Panel N156BGE-L21), MYSTERY MTV-1629LW (Panel N156BGE-L21), SUPRA STV-LC16741WL (Panel NT156WHM-N12), SUPRA STV-LC16740WL (Panel LTN156AT32).
Main features of the DEXP 16A3000 device:
The matrix (LED panel) N156BGE-L2 1366x768 WXGA is installed.
An integrated LED driver is used to power the backlight LEDs.
To power all the internal components of the DEXP 16A3000 TV, an external adapter 12V type is used.
MainBoard - the main board (motherboard) is a CVMV29L-F module, using Cpu chips: TSUMV59XU-Z1, SPI Flash - 25Q32FVSIG, AUDIO: NS4263 and others.
The tuner CDT-3NP5I1-10 provides the reception of television programs and tuning to channels.

 Trademark: DEXP, Model: 16A3000.
Briefly from the TV: LCD, LED backlight, 16 ", 1366x768, 720p HD, sound: 10 watts.
The composition uses MainBoard CVMV29L-F and LCD panel (matrix) N156BGE-L2 1366x768 WXGA.
Power supply unit external Adapter 12V.
Technical description
DEXP 16A3000 TV with N156BGE-L2 LCD, 16 "(41 cm) diagonal size of 16: 9 format. The required screen brightness of 200 cd / m² is provided by LED backlight LED. Contrast - the ratio of maximum brightness to minimum is 1000: 1. This model uses a panel with the end position of the backlight LEDs - Edge LED. You can watch broadcasts and movies and images in high quality HD at a resolution of 1366x768 pixels in the standard of graphic decomposition 720p (HD Ready). The input high-frequency or video signal is decoded into analog PAL, SECAM, NTSC og systems.Graphic processing and digital signal generation takes place in the standards 480i, 480p, 576i, 576p, 720p.
The power of the sound system 10 W (2x5 W) provides 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, VGA, HDMI, 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, 1360x768.
Overall dimensions: 375x239x40 mm.
Attention! The N156BGE-L2 1366x768 WXGA panel of the DEXP 16A3000 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.