Technical description and composition of the TV TCL F40B3803, type of panel and applicable modules. The composition of the modules.TCL LED
Model: F40B3803
Chassis / Version: 40-MT31EPA-MAC2HG
Panel: V400HJ6-PE1 Rev. C2
LED driver (backlight): integrated into MainBoard
PWM LED driver: MP3398A
MOSFET LED driver: AOD256
Power Supply (PSU): integrated into MainBoard
PWM Power: RT7736B
MOSFET Power: MDF10N65B
MainBoard: 40-MT31EPA-MAC2HG
IC MainBoard: SPI Flash: W25Q64FVSIG
Tuner: ST34WN-2T-E
Technical Specifications F40B3803
TCL F40B3803
General repair guidelines for TV LCD LED
Possible manifestations of defects
- The TCL F40B3803 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.
The malfunction in such cases should first 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 40-MT31EPA-MAC2HG main board. It is necessary to measure the output voltages in its secondary circuits, and if they are completely absent, check the serviceability of power switches (MDF10N65B) and rectifier diodes for possible breakdown (short circuit).
In case of breakdowns of semiconductors in the secondary circuits, the converter can usually work abnormally in the short circuit mode, and during short circuit in the power elements of the primary circuit, the mains fuse 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 circuits (OOS) of stabilization. PWM controllers (PWMs) of the RT7736B, if they do not have visible damage to the chassis and open fault between the terminals, are usually checked by replacement.
- 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.
As a rule, in such cases there is no display 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.
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 malfunction, the zener diode PN junction 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 40-MT31EPA-MAC2HG 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 SPI Flash microcircuits: W25Q64FVSIG 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.
Before changing the ST34WN-2T-E tuner, if it is not possible to tune to television channels, make sure that there are supply voltages that must be measured at the corresponding tuner pins and checked for correctness. The pulses of the data exchange of the tuner with the processor can be controlled by an oscilloscope
TV users and owners must remember that attempts to self-repair a TCL F40B3803 TV without the appropriate qualifications and necessary experience can lead to serious negative consequences!
FIRMWARE FOR SPI FLASH -----------> TCL F40B3803, Main: 40-MT31EPA-MAC2HG, Panel: V400HJ6-PE1 Rev.C2
To reduce the backlight current, the total resistance of the resistors relative to the housing on the ISET pin of the MP3398A should be proportionally increased. ISET (current setting) - pin 8 in the SOIC-20 package or pin 6 in the SOIC-16 package.
The appearance of the MainBoard 40-MT31EPA-MAC2HG is shown in the figure below:40-MT31EPA-MAC2HG
40-MT31EPA-MAC2HG can be used in TVs:
TCL F40B3804 (Panel LVF400CMDX E1 V2), TCL F40B3803 (Panel V400HJ6-PE1 Rev.C2).
Main features of the TCL F40B3803 device:
Installed matrix (LED-panel) V400HJ6-PE1 Rev.C2.
To power the backlight LEDs, a converter is used, combined with the main board 40-MT31EPA-MAC2HG, controlled by the MP3398A PWM controller. As the power elements of the LED driver, keys of the AOD256 type are used.
The power module is combined with the MainBoard and is made according to the flyback AC / DC voltage converter circuit using RT7736B microcircuits and power switches of the MDF10N65B type.
MainBoard - the main board (motherboard) is a 40-MT31EPA-MAC2HG module, using SPI Flash chips: W25Q64FVSIG and others.
The ST34WN-2T-E tuner provides television reception and channel tuning.
Additional technical information about the panel:
Brand: INNOLUX
Model: V400HJ6-PE1 Rev. C2
Type: a-Si TFT-LCD, CELL
Diagonal size: 40 inch
Resolution: 1920x1080, FHD
Display Mode: MVA, Normally Black, Transmissive
Active Area: 878.112x485.352 mm
Surface: Antiglare (Haze 1%)
Glass Depth: 0.50 + 0.50 mm
Transmissivity: 6.0% (with Polarizer)
Contrast Ratio: 5000: 1
Display Colors: 16.7M (8-bit)
Response Time: 8.5 (G to G)
Frequency: 60Hz
Signal Interface: LVDS (2 ch, 8-bit), 51 pins
Voltage: 12.0V
TCL F40B3803 TV with V400HJ6-PE1 LCD display, diagonal size 40 "(102 cm) in 16: 9 format. The brightness of the screen declared by the manufacturer, 310 cd / m² is realized by LED backlighting. The LED technology in the manufacturing technology of the screen of this TV model is realized by LED LED The design and technical capabilities of the TV include watching programs and movies in high quality HD at a resolution of 1920x1080 pixels in graphic resolution according to the standard 1080p (Full HD). The input high-frequency or video signal can be processed in analog x PAL, SECAM, NTSC systems. Graphic processing and digital signal generation occurs in the standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p. Supported media file formats: MP3, WMA, MPEG4, JPEG.
The power of the sound system 32 W (2x16 W) provide two speakers. It uses a NICAM stereo signal processing system and Sound Surround.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), SCART, HDMI x2, MHL, USB, Ethernet (RJ-45). 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.
The power consumed by the TV in the operating mode from the network is 50 watts.
Overall dimensions: with stand 908x565x240 mm, without stand 908x530x87 mm.
The mass of the TV: 7.2 kg.
Attention! The panel of the V400HJ6-PE1 Rev.C2 LED-TV TCL F40B3803 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.
