Saturday, 12 September 2020

REPAIRING / SERVICING TV THOMSON T40ED06HU

Technical description and composition of the THOMSON T40ED06HU TV, panel type and modules used. The composition of the modules.
THOMSON LED
Model: T40ED06HU T40ED06HU-01B
Chassis / Version: TP.MS18VG.P78
Panel: LVF400SSDX E7 V2
LED backlight: Led DRV 75V
T-CON: 14Y-GA-40FMB7S4LV0.2
LED driver (backlight): integrated into MainBoard
PWM LED driver: OB3363QPA
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MainBoard: TP.MS18VG.P78 3MS82AX
IC MainBoard: CPU: MST3M182VGC-LF -Z1, Spi Flash: 25Q32, EEPROM: 24C32, AUDIO: TPA3110LD2
Tuner: R620D
Specifications T40ED06HU
THOMSON T40ED06HU
General recommendations for TV LCD LED repair
Possible manifestations of malfunctions
- THOMSON T40ED06HU TV does not turn on. There are no signs of operability. The indicators on the front panel do not light or blink, the TV does not respond to the remote control and control buttons.
A malfunction in such cases should be looked for in the elements of the power source - the mains voltage converter (AC / DC), which is located on the main board MainBoard TP.MS18VG.P78. It is necessary to make sure that its output voltages are present and, if they are completely absent, check the power switches and rectifier diodes for a possible short circuit.
In the event of diode breakdowns in the secondary circuits, the converter can operate in an emergency mode of short circuit without output voltages, and in the event of a short circuit in the power elements of the primary circuit, the mains fuse and / or the current sensor in the source of the key usually breaks off.
Mos-Fet power switches used in switching power supplies sometimes fail due to a malfunction of any other elements that can disable it in the key mode, or create an excess of the maximum permissible key parameters. These can be elements supplying a PWM regulator, frequency setting or damper circuits, or elements of negative feedback in the stabilization circuit. PWM controllers PWM SOT23-6, in the absence of visible damage or outright short circuits between the terminals, are checked by replacing them with new ones, or known to be working properly.
- There is no image, there is sound, it reacts to the remote control, the channels are switched. In some cases, the image appears when turned on and disappears immediately.
The most likely problem in these cases is a malfunction of the LED backlight. The reason may 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 is impossible to check the LED bars for a break without disassembling the panel with a multimeter or tester. For these purposes, it is necessary to open all series-connected PN junctions and a voltage of the order of tens of volts is required, and ideally a current source. Having disassembled the panel, it is necessary to check each LED separately. Chinese multimeters tend to light one 3-volt LED in the forward direction. In the case of using dual 6-volt LEDs, the PN junction of its protective zener diode can serve as an indicator of serviceability. In faulty LEDs, the zener diode will either be cut off or broken through in the K / Z.
- The TV does not go into operation, does not respond to the remote control. The indicator on the front panel is on or blinking.

 If the THOMSON T40ED06HU has no image, but there is sound, often the display backlight LVF400SSDX E7 V2 simply does not work. Moreover, in LED TVs, the LEDs inside the panel usually fail, less often the LED driver.
In such cases, you can see a barely noticeable image with a successful hit of external light on the screen.
Replacing the LEDs requires disassembling the LVF400SSDX LCD panel - a process that requires experience and qualifications from the master. We do not recommend doing such work on your own to the owners of TVs and craftsmen who do not have experience in repairing LCD panels
If there is no image, and the backlight is on, the screen becomes slightly lighter when turned on, and in an open TV you can see light through the holes in the panel case.
In this case, the panel may also be faulty - damage to the strips, loops, for example, as a result of moisture ingress after unsuccessful washing of the screen, the T-CON (Timing Controller) board may be faulty. But the main board MainBoard TP.MS18VG.P78 often turns out to be faulty, a software failure is also possible.
Then, first of all, it is necessary to check the panel supply voltage, fuses on the T-CON board, as well as the supply and reference voltages of the column and line drivers - VGH, VGL, Vcom.
If these measurements are within the normal range, it is necessary to use an oscilloscope to trace the passage of LVDS signals from MainBoard TP.MS18VG.P78, as well as synchronizing signals to loops with drivers.
Flooded or unsuccessfully washed screens of LED TVs can be restored, in about half of the cases, usually if significant damage has not formed in the loops and panel strips.

Repair or diagnostics of the TP.MS18VG.P78 motherboard should begin with checking the stabilizers and power converters necessary to power the microcircuits and matrix. If necessary, you should update or replace the software (software). Repair of the board and replacement of CPU chips: MST3M182VGC-LF -Z1, Spi Flash: 25Q32, EEPROM: 24C32, AUDIO: TPA3110LD2 are made if the necessary equipment and the corresponding element base are available. Malfunctions associated with the use of BGA soldering technologies can be localized by the warm-up method.
The malfunction of the R620D tuner is established after checking the software and all supply voltages at its terminals. The data exchange of the tuner with the processor via the I2C bus can be monitored with an oscilloscope.
Users and owners of TVs should remember that attempts to self-repair a THOMSON T40ED06HU TV without appropriate qualifications and the necessary experience can lead to serious negative consequences!


DOWNLOAD FIRMWARE FOR SPI FLASH  ----------->   THOMSON T40ED06HU T40ED06HU-01B, Main: TP.MS18VG.P78 3MS82AX, Panel: LVF400SSDX E7 V2



 To reduce the backlight current in LED drivers with OB3363QP (16 pin) controller, the total resistance of the resistors from pin 5 (ISET) to the case should be proportionally increased.
https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhccEeX0aT5BOgdFGdJUUcP8U0ZazbEA5fz_sE9S41xBPnn8La_Lt0Cfc0y_7l4EWgbTJge3rSe97GDdBhA0DnZ_ZImv91VC4YQhLLnqRb-xO3fgW3QdRN4iZrIf1iYeeA1MhyDgLeOznA/s1600/TP.MS18VG.P78_DCE.jpg

Additional MainBoard Repair
The appearance of MainBoard TP.MS18VG.P78 is shown in the figure below:
TP.MS18VG.P78
TP.MS18VG.P78 can be used in TVs:
THOMSON T42E02HU-01B (Panel LVF420AUDX E8 V1), THOMSON T32ED05U-01B T32ED05U (Panel LVW320CSDX E3 V7), THOMSON T32E02U-01B (Panel A320HE2A05-7A), THOMSON T40ED06HU T40ED06HU-01B (Panel LVF400SSDX E7 V2).
The main features of the THOMSON T40ED06HU device:
Installed matrix (LED panel) LVF400SSDX E7 V2.
Matrix control uses Timing Controller (T-CON) 14Y-GA-40FMB7S4LV0.2.
To power the backlight LEDs, a converter combined with the main board TP.MS18VG.P78 is used, controlled by the OB3363QPA PWM controller.
The power module is combined with the MainBoard and is made according to the AC / DC flyback voltage converter using PWM SOT23-6 microcircuits.
MainBoard - the main board (motherboard) is a TP.MS18VG.P78 module, using CPU chips: MST3M182VGC-LF -Z1, Spi Flash: 25Q32, EEPROM: 24C32, AUDIO: TPA3110LD2 and others.
The R620D tuner provides reception of television programs and tuning to channels.

 

PWM SMPS in SOT-23-6, SOT-26, TSOP-6 packages

In the circuitry of modern switching power supplies (SMPS), PWM controllers made in small-sized planar packages with six terminals have gained wide popularity. The enclosure type designation can be SOT-23-6, SOT-23-6L, SOT-26, TSOP-6, SSOT-6. The appearance and arrangement of the pins are shown in the figure below. In this case, the code marking LD7530A is shown on the left fragment of the picture.


 

 Pin assignment:
1 - GND. (Common wire).
2 - FB. (FeedBack - Feedback). Input for controlling the duration of pulses with a signal from the output voltage. Sometimes it can be labeled COMP (input comparator).
3 - RI / RT / CT / COMP / NC - Depending on the type of microcircuit, it can be used for a frequency-setting RC circuit (RI / RT / CT), or for organizing protection, as an input of a PWM trip comparator at a threshold value at its input, specified in the document. In some types of microcircuits, this input may not be used in any way (NC - No Connect).
4 - SENSE, otherwise CS (Current Sense) - Input from the current sensor at the source of the key.
5 - VCC - Input voltage supply and start of the microcircuit.
6 - OUT (GATE) - Output for controlling the gate (Gate) of the key.

Functionally, these regulators work on the principle of the previously popular xx384x PWM microcircuits, which have proven themselves well in terms of reliability and stability.

Some difficulties often arise when replacing or choosing an analog for such PWM regulators due to the use of code markings in the designation of the type of microcircuits. The situation is complicated by a large number of component manufacturers who do not always provide documentation to the mass access, just as not all manufacturers of finished devices supply repair service centers with diagrams, so repairmen often have to study real circuit solutions by installed components and wiring connections directly on the board.

In practice, PWM microcircuits and the marking code EAxxx and Eaxxx are often found. Official documentation for them was not found in the public domain, but discussions on the forums and pieces of pictures from PDF from System General, which publishes them as SG6848T and SG6848T2, have survived. The drawing is here placed left .


 

For the attention of the masters, here below are PDF datasheet tables compiled from information available on the Internet and PDF documents for the selection of analogues types when replacing the most common six-legged planar PWM with pinout pins: pin1 - GND, pin2 - FB (COMP), pin4 - Sense, pin5 - Vcc, pin6 - OUT ...
Their main difference is the application and purpose of pin 3. 

 

NamePart NumberFabricantMarking
SG6849SG684965TZFairchild / ON SemiBBxx
SG6849SG6849-65T, SG6849-65TZSystem GeneralMBxx EBxx
SGP400SGP400TZ System General AAKxx

 

 PWM controllers (PWM) with a 95-100 kOhm resistor on pin 3.

When applying the PWM listed below, the frequency should be set with the RT (RI) resistor from pin 3 to ground. Usually its nominal value is chosen 95-100 kOhm for a frequency of 65-100 KHz. For more details, see the here below attached documentation. PDF files are packed in RAR.

 

NamePart NumberFabricantMarking
AP3103AAP3103AKTR-G1Diodes IncorporatedGHL
AP8263AP8263E6R, A8263E6VRAiT SemiconductorS1xx
AT3263AT3263S6ATC Technology3263
CR6848CR6848SChip-Rail848H16
CR6850CR6850SChip-Rail850xx
CR6851CR6851SChip-Rail851xx
FAN6602RFAN6602RM6XFairchild / ON SemiACCxx
FS6830FS6830FirstSemi
GR8830GR8830CGGrenergy30xx
GR8836GR8836C, GR8836CGGrenergy36xx
H6849H6849NFHI-SINCERITY
H6850H6850NFHI-SINCERITY
HT2263HT2263MPHOT-CHIP63xxx
KP201
Kiwi Instruments
LD5530LD5530GL LD5530RLeadtrandxxt30 xxt30R
LD7531LD7531GL, LD7531PLLeadtrendxxP31
LD7531ALD7531AGLLeadtrendxxP31A
LD7535/ALD7535BL, LD7535GL, LD7535ABL, LD7535AGLLeadtrendxxP35-xxx35A
LD7550LD7550BL, LD7550ILLeadtrendxxP50
LD7550BLD7550BBL, LD7550BILLeadtrend xxP50B
LD7551LD7551BL/ILLeadtrendxxP51
LD7551CLD7551CGLLeadtrendxxP51C
NX1049XN1049TPXian-Innuovo49xxx
OB2262OB2262MPOn-Bright-Electronics62xx
OB2263OB2263MPOn-Bright-Electronics63xx
PT4201PT4201E23FPowtech4201
R7731R7731GE/PERichtek0Q=
R7731AR7731AGERichtekIDP=xx
SD4870SD4870TRSilan Microelectronics4870
SF1530SF1530LGTSiFirst30xxx
SG5701SG5701TZSystem GeneralAAExx
SG6848SG6848T, SG6848T1, SG6848TZ1, SG6848T2Fairchild / ON SemiAAHxx EAxxx
SG6858SG6858TZFairchild / ON SemiAAIxx
SG6859ASG6859ATZ, SG6859ATYFairchild / ON SemiAAJFxx
SG6859SG6859TZFairchild / ON SemiAAJMxx
SG6860SG6860TYFairchildAAQxx
SP6850SP6850S26RGSporton Lab850xx
SP6853SP6853S26RGB, SP6853S26RGSporton Lab853xx
SW2263SW2263MPSamWin
UC3863/GUC3863G-AG6-RUnisonic Technologies CoU863 U863G
XN1049XN1049, XN1049TPInnuovo Microelectronics49 xxx

 

 PWM controllers that use pin 3 differently.

When using the following PWM (PWM controllers), you should pay attention to pin 3, which can be used to organize protection - thermal or from overvoltage of the input voltage.
The frequency can be fixed at 65kHz, or set by the value of the capacitor at pin 3.
When replacing any microcircuits with analogs, carefully study the documentation. PDF files are packed in a RAR archive.

 

NamePart NumberFabricantMarking
AP3105/V/L/RAP3105KTR-G1, AP3105VKTR-G1, AP3105LKTR-G1, AP3105RKTR-G1Diodes IncorporatedGHN GHO GHP GHQ
AP3105NA/NV/NL/NRAP3105NAKTR-G1, AP3105NVKTR-G1, AP3105NLKTR-G1, AP3105NRKTR-G1Diodes IncorporatedGKN GKO GKP GKQ
AP3125A/V/L/RAP3125AKTR-G1, AP3125VKTR-G1, AP3125LKTR-G1, AP3125RKTR-G1Diodes IncorporatedGLS GLU GNB GNC
AP3125BAP3125BKTR-G1Diodes IncorporatedGLV
AP3125HA/HBAP3125HAKTR-G1, AP3125HBKTR-G1Diodes IncorporatedGNP GNQ
AP31261AP31261KTR-G1Diodes IncorporatedGPE
AP3127/HAP3127KTR-G1, AP3127HKTR-G1Diodes IncorporatedGPH GSH
AP3301AP3301K6TR-G1Diodes IncorporatedGTC
FAN6862FAN6862TYFairchild / ON SemiABDxx
FAN6863FAN6863TY, FAN6863LTY, FAN6863RTYFairchild / ON SemiABRxx
HT2273HT2273TPHOT-CHIP73xxx
LD7510/JLD7510GL, LD7510JGLLeadtrendxxP10 xxP10J
LD7530/ALD7530PL, LD7530GL, LD7530APL, LD7530AGLLeadtrendxxP30 xxxP30A
LD7532LD7532GLLeadtrendxxP32
LD7532ALD7532AGLLeadtrendxxP32A
LD7532HLD7532HGLLeadtrendxxP32H
LD7533LD7533GLLeadtrendxxP33
LD7536LD7536GLLeadtrendxxP36
LD7536RLD7536RGLLeadtrendxxP36R
LD7537RLD7537RGLLeadtrendxxP37R
LD7539C GLLD7539C GLLeadtrendxxP39C
ME8204ME8204M6GMicrOneME8204xx
NCP1250NCP1250ASN65T1G, NCP1250BSN65T1G, NCP1250ASN100T1G, NCP1250BSN100T1GON Semiconductor25xxxx
NCP1251NCP1251ASN65T1G, NCP1251BSN65T1G, NCP1251ASN100T1G, NCP1251BSN100T1GON Semiconductor5xxxxx
OB2273OB2273MPOn-Bright-Electronics73xx
R7735R7735AGE, R7735HGE, R7735GGE, R7735RGE, R7735LGERichtek
UC3873/GUC3873-AG6-R, UC3873G-AG6-RUnisonic TechnologiesU873 U873G

 

 

 


LED TV THOMSON T40ED06HU with LCD LVF400SSDX, diagonal size 40 "(102 cm) 16: 9 format. The declared brightness of the screen is 320 cd / m2 provided by modern LED backlight LED. The ratio of maximum brightness to minimum (contrast) is not less than 4000 : 1. The LCD panel adopts Direct LED backlighting with backlighting The design and technical capabilities of the TV allow viewing in high quality HD at a resolution of 1920x1080 pixels in graphic resolution in 1080p (Full HD). Input high-frequency or video signal is decoded into analog systems PAL, SECAM, NTSC Formation of digital signal (graphic format) is performed in the standards 480i, 480p, 576i, 576p, 720p, 1080i, 1080p Multimedia formats are supported: MP3, WMA, MPEG4, Xvid, MKV, JPEG.
Speaker power 16 W (2x8 W) is provided by two speakers. The NICAM STEREO audio processing system is used.
External interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, component, VGA, HDMI x3, USB. A standard VGA (D-Sub 15) connector is used to connect a laptop or computer. This interface supports resolutions: 640x480, 800x600, 1024x768, 1280x1024, 1360x768, 1920x1080.
Dimensions: with stand 924x612x210 mm, without stand 924x555x93 mm.
TV weight: with stand: 13 kg, without stand: 10.3 kg.
Attention! The LVF400SSDX E7 V2 panel of the THOMSON T40ED06HU LED TV is an expensive and unreliable element.
Do not allow any impact on the glass and pressure on the screen surface to avoid damage to the LED panel!
It is also unsafe for liquid to spill onto the screen. Sometimes one drop is enough if it drips down the glass onto the cables to make the TV unrepairable.