Thursday, 17 September 2020

REPAIRING / SERVICING TV SUPRA STV-LC1504W

Technical description and composition of the SUPRA STV-LC1504W TV, panel type and modules used. The composition of the modules.
SUPRA
Model: STV-LC1504W
Chassis / Version: JUG7.820.510-5
Panel: HT156WX1-100
Inverter (backlight): WYIV-009
PWM Inverter: TL494
MOSFET Inverter: ME4542
Power Supply (PSU): AYP160001
PWM Power: PWM SOT23-6
MOSFET Power: FQPF6N60C
MainBoard: JUG7.820.510-5
IC MainBoard: CPU: MST718BE-LF; TEA2025B LA72700 PT2314 MX25LV016 AOZ8006 TDA9885T / TDA9886T MP2309 MP1484
Tuner: TAF6-C2121VH
STV-LC1504W Specifications
SUPRA STV-LC1504W
General recommendations for TV LCD repair
SUPRA with JUG7.820.510-2 chassis, like other TVs, it is advisable to start repairing with a careful examination of external and internal elements and modules. According to some external signs of a change in the state of some elements, it sometimes becomes possible to make assumptions about the nature of the defect, as well as to determine the further direction of troubleshooting. If ring cracks are found in the soldering of the terminals of the elements or broken connecting tracks, swollen capacitors or charred resistors - all this may be characteristic signs of the causes or consequences of an already known typical malfunction.
If the TV does not turn on, none of the indicators on its front panel will light or blink. Also, if the TV does not respond to the remote control and buttons, does not emit any sounds and any signs of operability when turned on, there is a certain probability that the FSP048-2PI04 power supply module is faulty and needs repair. Sometimes a problem with similar manifestations can occur only in the absence of processor power, which is typical for certain SUPRA models. The first step is to replace the swollen capacitors of the rectifier filters, if any. If the mains fuse in the power supply is broken, in most cases a breakdown of the power switch (s) is detected, which can be integrated with the PWM controller, or a separate field-effect transistor can be used. You should also check the diodes of the rectifier bridge and the electrolytic capacitor of the mains rectifier filter.
Power switches in switching power supplies (SMPS) fail for no reason very rarely and, in case of their breakdown, it is necessary to look for a malfunction in the stabilization circuits by checking electrolytic capacitors, semiconductor devices and resistors in the primary circuit. The reason may be a malfunction of the STRW6525 PWM regulator microcircuit, which can only be checked by replacing it with a new or known good one.
If, when SUPRA STV-LC1904W is turned on, there is no image, or it appears for a second and disappears altogether, but there is sound, most likely either the backlight lamps or their power converter (inverter) are faulty. It is necessary to check the electrolytic capacitors of the filter of the secondary rectifiers in the common power supply.
The operation of the power circuits of the inverter and the backlight lamps in the normal mode is controlled by special protection, which is organized for fire safety purposes, for example, to disconnect when short circuits or breaks in high-voltage connections or when lamps are depressurized. This protection makes it difficult to diagnose and repair the inverter.





The SUPRA STV-LC1504W has no picture when there is a signal is often caused by a malfunction of the display backlight. Moreover, the problem can be both inside the LCD panel (matrix) HT156WX1-100, for example, a malfunction of CCFL (EEFL) lamps, and outside in their power source - an inverter.
Without backlighting, sometimes you can see a barely noticeable image with a certain successful hit of external light on the screen.
Often, to repair the backlight, disassembly of the HT156WX1-100 LCD panel is required - a painstaking process that requires special attention and accuracy from the master. In such cases, there is a possibility, with the slightest negligence, to damage the glass or loops and the TV may become unrepairable.
We strongly do not recommend doing such work to owners of TVs and craftsmen who do not have experience in repairing LCD panels! Moreover, at home (at the owner's home).
If there is no image in the presence of backlight, the screen becomes slightly lighter when turned on, and if the TV is open, the light from the lamps can be seen through the holes in the panel case.
In this case, there may be a malfunction inside the panel, damage to strips, loops, the T-CON board (Timing Controller) may be defective. But often the main board MainBoard JUG7.820.510-5 also turns out to be faulty, a software failure is also possible.
In such cases, the master first of all needs to check the main supply voltage of the panel at the LVDS connector, the fuses on the T-CON board or the panel brackets, as well as the supply and reference voltages for the line and column drivers - VGH, VGL, Vcom.
If all of the above measurements are within the normal range, then the oscilloscope must track the passage of LVDS signals from MainBoard JUG7.820.510-5, as well as synchronizing signals from T-CON to loops with drivers.

Repair or diagnostics of the JUG7.820.510-2 motherboard should begin with checking the stabilizers or power converters of its microcircuits. If necessary, you should update the software (software). Repair of the board and replacement of microcircuits MST718BE-LF, 24LC32, 4803A, CSC2314F, TEA2025B are performed 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.
Once again, we remind TV users: do not try to repair yourself without the appropriate knowledge, experience and the necessary qualifications! Entrust repairs only to professionals with sufficient experience in the field of electronic repair.

DOWNLOAD SCHEMATIC DIAGRAM  / SERVICE MANUAL   ------------------>    JUG7.820.510-2 MST718BE for  STV-LC1904WD, STV-LC1910W, STV-LC2211WD 



DOWNLOAD FIRMWARE FOR SPI FLASH  ----------->  SUPRA STV-LC1910W, Cpu: TSUMV26KU-LF, Flash: F40-100G, Tuner: TAF6-C2121VH 0406BB, Audio: YD1517P, Power: IC101 - LD7575, U2 - AO4516, IC1 - TL494

 The appearance of MainBoard JUG7.820.510-5 is shown in the figure below:
JUG7.820.510-5
JUG7.820.510-5 can be used in TVs:
SUPRA STV-LC1504W (Panel HT156WX1-100), SUPRA STV-LC1910W (Panel HT185WX1-100).
External view of the power supply
Main features of SUPRA STV-LC1504W device:
Installed matrix (LCD panel) HT156WX1-100.
To power the backlight lamps, the WYIV-009 inverter is used, controlled by the TL494 PWM controller. As the power elements of the inverter, keys of the ME4542 type are used.
The formation of the necessary supply voltages for all nodes of the SUPRA STV-LC1504W TV is carried out by the AYP160001 power module, or its analogs using PWM SOT23-6 microcircuits and FQPF6N60C power switches.
MainBoard - the main board (motherboard) is a JUG7.820.510-5 module, using CPU chips: MST718BE-LF; TEA2025B LA72700 PT2314 MX25LV016 AOZ8006 TDA9885T / TDA9886T MP2309 MP1484 and others.
The TAF6-C2121VH 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

 

 



LCD TV SUPRA STV-LC1504W with LCD HT156WX1-100, 15 "4: 3 format diagonal. Screen brightness of 250 cd / m² is provided by CCFL (EEFL) fluorescent lamps. Contrast - ratio of maximum brightness to minimum is 500 : 1. The input high-frequency or video signal is decoded in analog systems PAL, SECAM, NTSC. Graphic processing and digital signal shaping takes place in the standards 480i, 480p, 576i, 576p.
The power of the acoustic system of sound 4 W (2x2 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, audio x2, S-Video, component, VGA. A headphone output is provided. To connect a computer or laptop to this TV model, a VGA (D-Sub 15) connector on the TV case is used, this interface supports resolutions: 640x480, 800x600, 1024x768.
The power consumed by the TV in operating mode from the network is 48 watts.
Dimensions: With stand 430x360x145 mm, Without stand 464x390x80 mm.
TV weight: 6 kg.
Attention! SUPRA STV-LC1504W LCD TV panel HT156WX1-100 is its most expensive component.

Avoid hitting the glass and putting pressure on the screen surface to avoid irreversible damage to the LCD panel!