Technical description and composition of the DEXP F43B8000H TV, type of panel and applicable modules. The composition of the modules.DEXP LED
Model: F43B8000H
Chassis / Version: RSAG7.820.6450
Panel: HE426HF-B51S6GM
LED backlight: SSY-1144579-A4718
T-CON: 42T34-C03 (T420HVN06.3 CTRL BD)
LED driver (backlight): integrated into MainBoard
PWM LED driver: PWM 16pin
MOSFET LED driver: N-FET
Power Supply (PSU): HLL-4855WA RSAG7.820.5687
PWM Power: NCP1271, NCP1608
MOSFET Power: 10N60, 8N65
MainBoard: RSAG7.820.6450 / ROH
IC MainBoard: 24C64
Tuner: HFT-96S1
Control: EN2U27D
Technical Specifications F43B8000H
DEXP F43B8000H
General repair guidelines for TV LCD LED
Possible manifestations of defects
- The DEXP F43B8000H TV does not turn on and does not show any signs of operability at all. There is no reaction to the remote control and control buttons from the front panel.
In such cases, the fault should be sought first in the HLL-4855WA power supply module. Then we recommend that you measure its output voltages and, if they are absent, you should check the health of the power switches (10N60, 8N65) and rectifier diodes of the converters for possible short circuit.
In case of any breakdown of semiconductors in the secondary circuits, the converter can usually work normally in emergency short circuit mode. There are no output voltages. And with a short circuit in the power elements of the primary circuit, as a rule, the mains fuse breaks and less often the current sensor at the source of the key.
The breakdown of Mos-Fet keys used in pulsed sources is often caused by malfunctions of other elements, for example, in the power supply circuit of a PWM controller, in frequency-setting or damping circuits, as well as in Negative Stabilization Feedback. PWM microcircuits NCP1271, NCP1608 are usually checked by replacing with new, or obviously working.
- 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.
The most likely in these cases is a malfunction of the LED backlight. The reason for this may be a break in the LED circuit, or a problem in stabilizing their power supply.
To detect a break in the LED lines without disassembling the panel, a current source is required. It is impossible to open transitions connected in series with a simple multimeter; voltage of several tens of volts is necessary.
- 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 RSAG7.820.6450 motherboard should begin by checking the stabilizers and power converters needed to power the microcircuit and matrix. If necessary, update or replace the software (software). Sophisticated MB board repair (SSB) is in some cases possible and practiced by repairmen. To do this, check and, if necessary, replace the 24C64 elements. BGA chip malfunctions are usually easy to detect by warming up.
If there is no reception of television channels, but the TV is working properly from external devices, first of all, check the voltage of the HFT-96S1 tuner and update the software. The pulses from the I2C bus must be controlled with an oscilloscope.
Owners and users of the DEXP F43B8000H 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!
SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> RSAG7.820.5687 Power supply
The appearance of the MainBoard RSAG7.820.6450 is shown in the figure below:RSAG7.820.6450
The appearance of the power supply
Main features of the DEXP F43B8000H device:
Installed matrix (LED-panel) HE426HF-B51S6GM.
The matrix control uses the Timing Controller (T-CON) 42T34-C03.
To power the backlight LEDs, a converter is used, combined with the main board RSAG7.820.6450, controlled by a PWM 16pin PWM controller. As the power elements of the LED driver, keys of the N-FET type are used.
The necessary supply voltages for all nodes of the DEXP F43B8000H TV are generated by the HLL-4855WA power supply module or its analogs using NCP1271, NCP1608 microchips and 10N60, 8N65 type power switches.
MainBoard - the main board (motherboard) is a RSAG7.820.6450 module, using 24C64 chips and others.
The HFT-96S1 tuner provides television reception and channel tuning.
DEXP F43B8000H TV with HE426HF-B51S6GM LCD, 43 "(109 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 3000: 1. 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 a graphic resolution according to the standard 1080p (Full HD).
The F43B8000H is equipped with SMART software, integrated applications and the ability to work on the Internet. Connecting to the Internet can be done via Wi-Fi. The input high-frequency or video signal is decoded in analog systems PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Supported media file formats: MP3, WMA, MPEG4, MKV, JPEG. Stereo sound is realized by two built-in 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, Ethernet (RJ-45), Wi-Fi. 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. A digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
Attention! The panel of the HE426HF-B51S6GM LED-TV DEXP F43B8000H 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.
