Saturday 18 April 2020

REPAIR / SERVICING TV DEXP F40B7000C

Technical description and composition of the DEXP F40B7000C TV, type of panel and applicable modules. The composition of the modules.
DEXP LED
Model: F40B7000C
Chassis / Version: TP.S512.PB83
Panel: C400F13-E2-C
LED backlight: RF-AB400E32-1001S-01
T-CON: V390HJ1-XRME
LED driver (backlight): integrated into MainBoard
PWM LED driver: SN510P
MOSFET LED driver: AOD4454
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MainBoard: TP.S512.PB83
IC MainBoard: CPU: S2T512, SPI Flash: 25Q64, Sound: TPA3110LD2, RT9108NB
Tuner: XF-3SDT-H (R840)
Technical Specifications F40B7000C
DEXP F40B7000C
General repair guidelines for TV LCD LED
Possible malfunctions
- The DEXP F40B7000C TV does not turn on, does not respond to the remote control and the control panel buttons, the indicators do not light or flash.
First of all, in such cases, you should verify the operability of the common switching power supply (IIP) - AC / DC voltage converter of the mains voltage. All source elements in this TV model are located on the MainBoard TP.S512.PB83 main board. 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 breakdowns in the secondary circuits, the converter can operate in a short circuit mode, and during short circuit in the elements of the primary circuit, the mains fuse usually breaks.
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 SOT23-6 PWM chips are usually checked by replacing with new ones, or obviously working.
- There is no image, but there is sound, it reacts to the remote control. Or the image appears when you turn it on and immediately disappears
In such cases, the most likely malfunction of the LED backlight elements. 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 blinks or lights constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the TP.S512.PB83 motherboard should begin by checking the stabilizers and power converters needed to power the microcircuits and matrix. If necessary, update or replace the software (software). Often, the MB (SSB) card must be replaced in case of complex malfunctions that are difficult to detect. When trying to repair, you should check its elements - CPU: S2T512, SPI Flash: 25Q64, Sound: TPA3110LD2, RT9108NB and replace failed chips with new ones. Some malfunctions may be due to the use of BGA soldering technologies in modern Main Board technologies. Typically, such defects are detected by local heating of the chip.
In the absence of tuning to the channels of on-air or cable television, you should make sure that the software is correct, as well as in accordance with the ratings of the supply voltage at the terminals of the tuner XF-3SDT-H (R840). It is also necessary to check the presence of pulses of data exchange between the tuner and the processor via the I2C bus using an oscilloscope.
For F40B7000C TV owners, we recommend that you contact qualified personnel with the necessary work experience for repairs! Self-repair attempts without the appropriate knowledge and skills can lead to irreversible negative consequences!

SCHEMATIC DIAGRAM  / SERVICE MANUAL   ------------------>    MainBoard TP.S512.PB83.

FIRMWARE FOR SPI FLASH  ----------->   DEXP F40B7000C, Main: TP.S512.PB83, Panel: C400F13-E2-C

  
 The appearance of MainBoard TP.S512.PB83 is shown in the figure below:
TP.S512.PB83
TP.S512.PB83 can be used in TVs:
AKAI LEA-39V51P (Panel LC390TA2A 902-P05-390H ), DEXP 40A7000 (Panel C400F13-E2-C), DEXP F39B7100E (Panel T390HVN04.0 CX390DLEDM), DEXP H32B7000C (Panel T320XVN02.9 C320X14-E2-A), DEXP F42B7000ED (Panel CX420DLEDM), DEXP F32C7000B (Panel BOEI320WU1), DEXP F32C7100B/W F32C7100 (Panel BOEI320WU1), DEXP 32A7000 (Panel BOEI320WU1), DEXP 42A7000 (Panel CX420DLEDM), DEXP F32B7000B (Panel BOEI320WU1), DEXP H39D7000E (Panel CX390DLEDM), DEXP F40B7000C (Panel C400F13-E2-C), DEXP H32B3200CD (Panel HV320WX2-201), HAIER LE28F6000T (Panel A275HD1A01-2 / LVW280CSDO E2 V2), HAIER LE32F6000T (Panel ST3151A05-8 LVW320CSDX E13 V2), MYSTERY MTV-4025LT2 (Panel CX400DLEDM), SHIVAKI STV-32LED13 (Panel SV320SHD PDL320TU2A X41), SHIVAKI STV-42LED16 (Panel V420HJ-P01), SHIVAKI STV-32LED14 (Panel CX315DLEDM AJ32TO3), SHIVAKI STV-40LED13W (Panel V400HJ6PE1-C2), SHIVAKI STV-32LED15 (Panel HV320WHB-N80), SUPRA STV-LC32T440WL (Panel C320X14-E13-H), SUPRA STV-LC32T900WL (Panel LC320TU3A), SUPRA STV-LC40T900FL (Panel 1080p Full HD 1920x1080), THOMSON T32D15DH-01B (Panel LVW320CSDX E13 V30), THOMSON T28D15DH-01B (Panel LVW280CSDE E3 V5), THOMSON T32D16DH-01W T32D16DH (Panel LVW320CSDX E19 V28), THOMSON T43D16SF-01B T43D16SF (Panel LVF430LGDO E2 V18).
Main features of the DEXP F40B7000C device:
Installed matrix (LED-panel) C400F13-E2-C.
The matrix control uses the Timing Controller (T-CON) V390HJ1-XRME.
To power the backlight LEDs, a converter is used, combined with the TP.S512.PB83 main board, controlled by the SN510P PWM controller. As power elements of the LED driver, keys of the AOD4454 type are used.
The power module is combined with the MainBoard and is made according to the flyback AC / DC voltage converter circuit using PWM SOT23-6 microcircuits.
MainBoard - the main board (motherboard) is
TP.S512.PB83 module, using CPU chips: S2T512, SPI Flash: 25Q64, Sound: TPA3110LD2, RT9108NB and others.
Tuner XF-3SDT-H (R840) provides the reception of television programs and tuning to channels.
Brand: DEXP, Model: F40B7000C.
Briefly from the TV: LCD, LED backlight, 40 ", 1920x1080, 1080p Full HD, DVR, sound: 20W, HDMI connectors: 3.
The composition uses MainBoard TP.S512.PB83 and an LCD panel (matrix) C400F13-E2-C. The power supply is combined with the MainBoard.
Technical description
DEXP F40B7000C TV with C400F13-E2-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. Dynamic contrast ratio of 5000: 1 is achieved by special control of the LEDs depending on the illuminance of sections in the plot.The LCD panel uses direct pixel illumination with rear LEDs - Direct LED. in high quality HD at a resolution of 1920x1080 pixels in graphic decomposition according to the standard 1080p (Full HD). The input high-frequency or video signal is decoded in analog systems PAL, SECAM, NTSC. Graphic processing and digital signal generation occurs in the standards 480i, 480p, 576i, 576p , 720p, 1080i, 1080p. Supported media file formats: MP3, MPEG4, MKV, JPEG.
The power of the acoustic system of sound 20 W (2x10 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, SCART, 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, 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 905x570x200 mm, without stand 905x522x97 mm.
TV Weight: with stand: 8.22 kg, without stand: 7.8 kg.
Attention! The C400F13-E2-C panel of a DEXP F40B7000C 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.