Technical description and composition of the DEXP F22B7000E TV, type of panel and applicable modules. The composition of the modules.DEXP LED
Model: F22B7000E / B
Chassis / Version: CV512L-B
Panel: CX215LEDM
LED backlight: EDGE LED
Power Supply (PSU): Adapter 12V
MainBoard: CV512L-B
IC MainBoard: CPU: S2T512, Spi Flash: 25Q64FVSIG, Audio: YD1517P
Tuner: T34WN-2T-E (TDA18275)
Technical Specifications F22B7000EE / A
DEXP F22B7000E
General repair guidelines for TV LCD LED
Possible manifestations of defects
- DEXP F22B7000E does not turn on, the indicators on the front panel do not light or flash. The TV does not respond to the control buttons and the remote control.
In such cases, the fault should be sought first in the Adapter power module.
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. Then we recommend that you measure its output voltages and, if they are absent, you should check the health of the power switches and rectifier diodes of the converters for a probable short circuit.
In case of any breakdowns in the secondary circuits, the converter can operate in emergency short-circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse or the current sensor at the source of the key more often 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 controllers, in the absence of visible damage or frank short-circuit between the terminals, are checked by replacing with new, or obviously working.
- 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.
Often in such cases, there is no LED backlight. 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.
To check the health in the LED circuit, it is better to use a current source with a maximum voltage of 200V. We do not recommend using any voltage sources for this purpose. You can check each LED individually with a simple Chinese multimeter (powered by 9 volts) in the P-N-junction test mode. If you connect the red probe of the multimeter to the anode of the LED, and the black to its cathode, then the 3-volt LED will light up slightly, and in the opposite direction you can detect the transition of the emergency zener diode. A zener diode PN junction indirectly indicates a LED-a
- 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 CV512L-B 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). Board repair and replacement of CPU chips: S2T512, Spi Flash: 25Q64FVSIG are carried out with the necessary equipment, and the corresponding element base. Faults associated with the application of BGA processor soldering technologies can be localized by the heating method.
If a tuner T34WN-2T-E (TDA18275) is suspected of malfunction, first of all, it is necessary to verify the correctness of the software, as well as the presence of the necessary power supply voltage levels and data exchange pulses with the processor via the I2C bus at the corresponding tuner pins.
Once again, remind users! Attempts to independently repair the DEXP F22B7000E TV without the appropriate qualifications and the necessary experience can lead to its complete non-repairability!
SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> Main CV512L-B
FIRMWARE FOR SPI FLASH -----------> DEXP F22B7000E/B, Main: CV512L-B, Panel: CX215LEDM
The appearance of the MainBoard CV512L-B is shown in the figure below:CV512L-B
CV512L-B can be used in TVs:
BBK 28LEM-1021/T2C (Panel SV275SHD HX010403 X41), BBK 22LEM-1026/FT2C (Panel M215HGE-P02), DEXP H24B7100E (Panel CX236LEDM (V236BJ1-P01)), DEXP F22B7000E/B (Panel CX215LEDM), ERISSON 22LEE31T2 (Panel CX215LEDM), RUBIN RB-22SE2FT2S (Panel 1080p Full HD 1920x1080), SUPRA STV-LC24T880WL (Panel HV236WHB-N00), SUPRA STV-LC22T880FL (Panel LC215DTBA).
Main features of the DEXP F22B7000E device:
Installed matrix (LED-panel) CX215LEDM.
To power all the internal components of the DEXP F22B7000E TV, an external adapter 12V type is used.
MainBoard - the main board (motherboard) is a CV512L-B module using CPU chips: S2T512, Spi Flash: 25Q64FVSIG, Audio: YD1517P and others.
The tuner T34WN-2T-E (TDA18275) provides the reception of television programs and tuning to channels.
TV DEXP F22B7000EE / A with an LCD display, diagonal size 22 "(56 cm) 16: 9 format. The required brightness of the screen is 250 cd / m² LED backlight LED. Contrast - the ratio of maximum brightness to minimum is 3000: 1. V This model uses a panel with the end position of the backlight LEDs - Edge LED.The TV features include viewing programs and movies in high quality HD at a resolution of 1920x1080 pixels in graphic resolution according to the standard 1080p (Full HD). Input high-frequency or video signal dec It is audible in analogue systems PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in the standards 480i, 480p, 576i, 576p, 720p, 1080i. Supported media file formats: MP3, MPEG4, JPEG.
The power of the sound system 6 W (2x3 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, 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, 1280x1024, 1360x768.
Overall dimensions: with stand 500x327x177 mm, without stand 500x303x54 mm.
TV Weight: with stand: 2.9 kg, without stand: 2.65 kg.
Attention! The DEXP F22B7000EE / A LED TV panel 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.