Technical description and composition of the DEXP F40B7200C TV, type of panel and applicable modules. The composition of the modules.Dexp
Model: F40B7200C
Chassis / Version: HLT57EJ
Panel: C400F14-E6-C (G5)
Lamp backlight: GDCH40LB06_LED3030_V0.4
Inverter (backlight): integrated into MainBoard
PWM Inverter: MP4012
MOSFET Inverter: MMD14N25
Power Supply (PSU): integrated into MainBoard
PWM Power: NCP1251 (PWM SOT23-6)
MainBoard: JUC7.820.00123957 HLT57EJ
IC MainBoard: CPU: 9206B, SPI Flash: GD25Q64, TPA3110D
Tuner: DMI21 C816RH / EDS-11170FNPRA / DMI21-C8I2RH
Technical Specifications F40B7200C
DEXP F40B7200C
General recommendations for repairing TV LCD
Possible malfunctions
- The DEXP F40B7200C TV does not turn on. There are no signs of operability. The indicators on the front panel do not light or flash, the TV does not respond to the remote control and control buttons.
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 JUC7.820.00123957 main board. It is necessary to measure the output voltages in its secondary circuits, and if they are completely absent, it is necessary to check the serviceability of power switches and rectifier diodes for possible breakdown (short circuit).
In case of breakdowns in the secondary circuits of the converter, it can usually fail in short circuit mode, and in case 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.
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 NCP1251 (PWM SOT23-6), in the absence of visible damage or frank fault 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, the channels are switched. In some cases, the image appears when you turn on and immediately disappears.
The defect can be caused by problems in the nodes or elements of the backlight of the display, or in the power supply of the lamps or the inverter.After checking all the electrolytic capacitors of the filters that are involved in the power supply of the inverter, you must ring in its converter power keys for breakdown and secondary windings of transformers for an open.
If in diagnosing a malfunction, it is necessary to disable the inverter protection, there is a risk of failure of the power elements of the inverter, and special care is required during work, and after they are finished, it is necessary to restore the protection circuits for further safe operation of the TV by the owner in normal mode.
- The TV does not turn on, the indicator indicates standby or operating mode, or blinks.
Repair or diagnostics of the JUC7.820.00123957 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: 9206B, SPI Flash: GD25Q64, TPA3110D 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 DMI21 C816RH / EDS-11170FNPRA / DMI21-C8I2RH tuner, if there is no tuning for the channels, first check the software and the supply voltage at its terminals. It is also necessary to make sure that the tuner and processor can exchange data via the I2C bus
Attention to users! Self-repair of a DEXP F40B7200C TV without the appropriate qualifications and the necessary experience can lead to its complete non-repairability!
FIRMWARE FOR SPI FLASH -----------> DEXP F40B7200C, Main: JUC7.820.00123957 HLT57EJ, Panel: C400F14-E6-C(G5)
The appearance of the MainBoard JUC7.820.00123957 is shown in the figure below:JUC7.820.00123957
JUC7.820.00123957 can be used in TVs:
DEXP F40B7200C (Panel C400F14-E6-C (G5)), SUPRA STV-LC40T440FL (Panel C400F15-E2-S (G01)), SUPRA STV-LC40T800FL (Panel C400F14-E8-C).
Main features of the DEXP F40B7200C device:
Installed matrix (LCD panel) C400F14-E6-C (G5).
To power the backlight, a converter is used, combined with the main board JUC7.820.00123957, controlled by the MP4012 PWM controller. As power elements of the inverter, keys of the type MMD14N25 are used.
The power module is combined with the MainBoard and is made according to the flyback AC / DC voltage converter circuit using NCP1251 microcircuits (PWM SOT23-6).
MainBoard - the main board (motherboard) is a JUC7.820.00123957 module, using CPU chips: 9206B, SPI Flash: GD25Q64, TPA3110D and others.
The tuner DMI21 C816RH / EDS-11170FNPRA / DMI21-C8I2RH provides the reception of television programs and tuning to channels.
DEXP F40B7200C TV with C400F14-E6-C LCD, 40 "(102 cm) diagonal size 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 3500: 1. The LCD panel uses direct backlighting of pixels with a rear LED arrangement - Direct LED.The TV features include viewing programs and movies in high quality HD at a resolution of 1920x1080 pixels in a graphic resolution of 1080p (Full HD) standard. Input high-frequency or video The signal is decoded in analogue systems PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in standards 480i, 480p, 576i, 576p, 720p. Supported media file formats: MP3, WMA, MPEG4, MKV, JPEG.
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 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, 1360x768. A digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
Overall dimensions: with stand 900x560x160 mm, without stand 900x520x88 mm.
TV Weight: with stand: 6.91 kg, without stand: 6.5 kg.
Attention! The C400F14-E6-C (G5) panel of a DEXP F40B7200C 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.