Technical description and composition of the DEXP F49B7000T TV, type of panel and applicable modules. The composition of the modules.DEXP LED
Model: F49B7000T
Chassis / Version: MSD6308-T8E
Panel: K490WD7
LED driver (backlight): integrated into PSU
PWM LED driver: AP3041M-G1
MOSFET LED driver: SMK630
Power Supply (PSU): K-PL-L01
PWM Power: L6562D, L6599AD
MainBoard: MSD6308-T8E
IC MainBoard: MSD6308RTEC-SW, 9F2G08ABAEA
Tuner: NoName MICRO
Technical Specifications F49B7000T
DEXP F49B7000T
General repair guidelines for TV LCD LED
Possible manifestations of defects
- The DEXP F49B7000T TV 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.
With such manifestations, in some cases, the K-PL-L01 power module is faulty. It is necessary to measure its output voltages, and in case of their absence, check the operability of the power switches of the converters and rectifier diodes for the probability of a 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.
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) L6562D, L6599AD, 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, but there is sound and reaction to commands from the remote control. Or the image appears immediately after turning on and disappears.
Usually in such cases, a malfunction is detected in the backlight nodes of the LED panel. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
It should be remembered that it is not possible to determine the open circuit in the LED lines without disassembling the panels with a tester or multimeter without an additional device, for example, a current source. To open all PN junctions connected in series at once, a voltage of several tens of volts may be required. Then it is necessary to open the panel and check each LED separately with a multimeter. If the capabilities of your multimeter do not allow you to open the LED in the forward direction or dual LEd are used, then the PN junction of the emergency zener diode can indirectly serve as a health indicator. In case of LED-a failure, the zener diode PN junction will either be cut off or broken into short-circuit.
- The TV does not enter the operating mode, does not respond to the remote control. The indicator on the front panel lights constantly or blinks.
Repair or diagnostics of the motherboard MSD6308-T8E 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 complex repairs of MB (SSB) and in the presence of the necessary skills and equipment, sometimes it may be necessary to replace its chips MSD6308RTEC-SW, 9F2G08ABAEA and other possible faulty components. Malfunctions associated with the application of BGA soldering technologies are usually easily diagnosed by the heating method.
The failure of the NoName MICRO tuner is established after checking the software and all the supply voltages at its terminals. The data exchange of the tuner with the processor via the I2C bus can be controlled by an oscilloscope.
It should be remembered! Attempts to independently repair the DEXP F49B7000T TV, in the absence of the necessary qualifications and experience, are categorically not recommended and are fraught with negative consequences, up to the complete non-repairability of the device!
The appearance of the MainBoard MSD6308-T8E is shown in the figure below:MSD6308-T8E
MSD6308-T8E can be used in TVs:
DEXP F42B7000T (Panel K420WD7), DEXP F55B7000T (Panel K550WD7).
The appearance of the power supply
Main features of the DEXP F49B7000T device:
Installed matrix (LED-panel) K490WD7.
To power the backlight LEDs, a converter is used, combined with a power supply unit, controlled by the AP3041M-G1 PWM controller. As power elements of the LED driver, keys of the SMK630 type are used.
The necessary supply voltages for all nodes of the DEXP F49B7000T TV are generated by the power module K-PL-L01, or its analogs using microcircuits L6562D, L6599AD.
MainBoard - the main board (motherboard) is an MSD6308-T8E module, using microchips MSD6308RTEC-SW, 9F2G08ABAEA and others.
The NoName MICRO tuner provides TV reception and channel tuning.
DEXP F49B7000T TV with K490WD7 LCD, 49 "(124 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 3500: 1. In LCD -panels use direct LED backlighting with direct 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 signal al 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, WMA, MPEG4, MKV, JPEG.
The power of the acoustic system of sound 20 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 x3, MHL, 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 1100x720x290 mm,.
Mass of the TV: 11.5 kg.
Attention! The K490WD7 panel of a DEXP F49B7000T 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.
