TELEFUNKEN LED
Model: TF-LED32S52T2S
Chassis/Version: MSA6285-ZC01-01
Panel: LSC320AN09-H
LED driver (backlight): integrated into MainBoard
PWM LED driver: AP3064 // OB3350
MOSFET LED driver: TO-252
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MOSFET Power: SMK0870F
MainBoard: MSA6285-ZC01-01
IC MainBoard: CPU: MSD6A628VX, SPI Flash: MX25L4006E, DC-DC: MSH6000A, RT7240
Specifications: NoName
TF-LED32S52T2S Specifications
TELEFUNKEN TF-LED32S52T2S
General advice about LCD LED TV repair
Possible faults
- TELEFUNKEN TF-LED32S52T2S TV set will not turn on or show any signs of trouble. No response to remote control or front panel control.
The trouble in such cases first of all shall be sought in the power elements of switching power supply (PPS) - AC/DC converter, which is combined with the MainBoard MSA6285-ZC01-01 in this TV model. It is necessary to measure its output supply voltages, and in case of their absence to check the operability of power keys (SMK0870F) of converters and rectifier diodes for the probability of breakdown in semiconductor PN-junctions.
If the diodes in the secondary circuits breakdown, the inverter may operate in emergency short-circuit mode without output voltages, and if the primary circuit power elements are shorted, the mains fuse and/or the current sensor at the source of the switch is usually blown.
The breakdown of power switches (MosFet) in switching supplies is sometimes caused by faults in other circuit elements, e.g. in the circuits supplying the PWM controller, the frequency pickup or damping circuits, as well as in the negative feedback (NF) stabilisation circuits. PWM regulators (PWM) PWM SOT23-6, unless they have visible housing damage and outright short circuits between pins, are usually checked by replacement.
- No picture, but there is sound and reaction to remote control commands. Or the image appears immediately after switching on and then disappears.
As a rule, in this case the LED panel backlight is defective. Often the cause is a breakage of the LEDs, or poor contact in the connectors plates, less often faulty can be the LED-driver.
It should be remembered that to determine the breakage in the LED line without disassembling the panel, using a tester or multimeter is not possible without an additional device, such as a current source. It may take several tens of volts to open all PN junctions connected in series at once. Then it is necessary to open the panel and check each LED separately with a multimeter. If the capacity of your multimeter does not allow to open the LED in the forward direction or twin LEd's are used, then the PN junction of the faulty stabiliser can indirectly be an indication of the functionality. If the LED is faulty, the PN junction of the stabiliser will either be open or shorted.
- The LED blinks or lights constantly, the TV does not switch on, the remote control is unresponsive.
Repair or diagnostic of MSA6285-ZC01-01 motherboard should start with checking stabilisers and power converters required for powering the microcircuits and matrix. Software (software) should be updated or replaced if necessary. Complex repair of MB board (SSB) is possible in some cases and practiced by repairers. You should check and if necessary replace CPU: MSD6A628VX, SPI Flash: MX25L4006E, DC-DC: MSH6000A, RT7240. BGA chip faults are usually easy to detect by warming up.
If the TV works normally from external devices, but does not tune to the TV channels, the NoName tuner might be faulty. In these cases you should first check that there is a supply voltage to the corresponding pins. Also make sure that the tuner and processor are communicating via the I2C bus. Sometimes a software malfunction can be the cause of a malfunction.
Attention TV Owners! Attempting to repair your TELEFUNKEN TF-LED32S52T2S by yourself is not recommended by the manufacturer and may cause serious damage.
DOWNLOAD SCHEMATIC DIAGRAM / SERVICE MANUAL ------------------> Chassis MSA6285-ZC01-01.
Warning. If there is an OB3363QP chip in the driver, take your time to verify it, it is most likely a mislabelled AP3064. A schematic is attached. Compare the documentation of both microcircuits.
Information from the laboratory.
Reduce backlight current from 450 mA to 320 mA - I removed 120 kOhm and left 47 kOhm at the ISET input of the AP3064 driver (pin 2) on the MSA6285-ZC01-01 board.
Limit the current to the driver. MSA6285-ZC01-01 and AP3064. General information
The driver may use the OB3350 chip. Then you can reduce the driver current with low impedance resistors in the LED circuit from the LED connector pins.
You can read more below:
Many TV manufacturers are now installing a questionable thermal rating for the backlight LEDs, which has a negative effect on the longevity of the device. In half of the cases, LEDs fail after 2-3 years of operation due to overheating, usually seen by the destroyed phosphor on the body of the LEDs. The warranty period, as a rule, the LEDs still have time to work out.
Even if the maximum allowable current is within specifications the cooling of LEDs is not always sufficiently efficient, which can be seen by the traces of overheating, i.e. dark spots on textolite slats on the back side. And modern LED televisions use diodes with an external phosphor coating, which after a year or two crumbles and the crystal directly shines purple. How such a source of ultraviolet radiation can harm the health of users, no one has yet thought.
Chinese manufacturers via Aliexpress supplies diodes and LED strips in kits of any assortment, but the lucky owner of the TV pays for them and for the repair.
After replacing one or more faulty LEDs, it is useful to look at the rest carefully, if the phosphor is cracked, it is advisable to replace all the LEDs. If you measure the voltage drop on overheated LEDs, it will be slightly higher than that of adjacent less worn or new LEDs, which indirectly indicates the presence of a parasitic active resistance (ESR). Further operation of such LEDs is even more questionable.
If you reduce the current in the diodes, the power dissipation and the real operating temperature will decrease, then there is a chance that the old ones will still work.
Ways to limit the current in LED backlight drivers:
There is a lot of information on the Internet about ways to limit the current in the LED backlighting for different TVs and LED drivers. A lot of it is written plausibly but sometimes it is written by people far from electronics in order to publish any popular content on hot topics to boost web-sites ratings.
It's impossible to talk about each case separately within one article, because even similar models may have different panels and different boards with their own driver variants. But there are basic principles that are clear to craftsmen with even minimal knowledge and skill.
Other popular, complex and controversial current limit cases will be published as information becomes available.
There are three basic ways to reduce the backlight current.
1. By increasing the resistance of the LED current sensor - a low-resistance measuring resistor in the cathode (LED-) circuit.
2. Increasing the ratings of the resistors on the ISET (current setting) input of the LED driver chip.
3. changing the resistor ratings in the divider on the ADIM (Dimming) control input.
The fundamental difference between input ISET and ADIM is that ISET - input inverted, as FB, and ADIM - direct.
To reduce the backlight current in LED drivers with AP3064 controller, increase the total resistance of the Rset resistor connected to pin 2 of ISET AP3064 relative to the housing. Calculated current value according to the documentation I[mA] = 1200/Rset[kOm].
If the LED driver chip is marked as OB3363QP - this is somebody else's mistake. In reality and according to the schematic it should be AP3064.
DOWNLOAD SCHEMATIC DIAGRAM LED drivers -----------> AP3064
DOWNLOAD SCHEMATIC DIAGRAM / SERVICE MANUAL ---------> Chassis MSA6285-ZC01-01
The appearance of the MainBoard MSA6285-ZC01-01 is shown in the figure below:
MSA6285-ZC01-01
Main features of the TELEFUNKEN TF-LED32S52T2S:
A matrix (LED panel) LSC320AN09-H is installed.
A converter combined with MSA6285-ZC01-01 main board, controlled by AP3064 // OB3350 PWM controller, is used to power the backlight LEDs. A TO-252-type switch is used as a power element in the LED driver.
The power module is combined with MainBoard and is designed as reverse-going AC/DC converter using PWM SOT23-6 chips and SMK0870F-type power switches.
MainBoard - motherboard is MSA6285-ZC01-01 module, with CPU: MSD6A628VX, SPI Flash: MX25L4006E, DC-DC: MSH6000A, RT7240 and other microchips.
The NoName tuner provides TV programme reception and channel tuning.
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.
| Name | Part Number | Fabricant | Marking |
|---|---|---|---|
| SG6849 | SG684965TZ | Fairchild / ON Semi | BBxx |
| SG6849 | SG6849-65T, SG6849-65TZ | System General | MBxx EBxx |
| SGP400 | SGP400TZ | 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.
| Name | Part Number | Fabricant | Marking |
|---|---|---|---|
| AP3103A | AP3103AKTR-G1 | Diodes Incorporated | GHL |
| AP8263 | AP8263E6R, A8263E6VR | AiT Semiconductor | S1xx |
| AT3263 | AT3263S6 | ATC Technology | 3263 |
| CR6848 | CR6848S | Chip-Rail | 848H16 |
| CR6850 | CR6850S | Chip-Rail | 850xx |
| CR6851 | CR6851S | Chip-Rail | 851xx |
| FAN6602R | FAN6602RM6X | Fairchild / ON Semi | ACCxx |
| FS6830 | FS6830 | FirstSemi | |
| GR8830 | GR8830CG | Grenergy | 30xx |
| GR8836 | GR8836C, GR8836CG | Grenergy | 36xx |
| H6849 | H6849NF | HI-SINCERITY | |
| H6850 | H6850NF | HI-SINCERITY | |
| HT2263 | HT2263MP | HOT-CHIP | 63xxx |
| KP201 | Kiwi Instruments | ||
| LD5530 | LD5530GL LD5530R | Leadtrand | xxt30 xxt30R |
| LD7531 | LD7531GL, LD7531PL | Leadtrend | xxP31 |
| LD7531A | LD7531AGL | Leadtrend | xxP31A |
| LD7535/A | LD7535BL, LD7535GL, LD7535ABL, LD7535AGL | Leadtrend | xxP35-xxx35A |
| LD7550 | LD7550BL, LD7550IL | Leadtrend | xxP50 |
| LD7550B | LD7550BBL, LD7550BIL | Leadtrend | xxP50B |
| LD7551 | LD7551BL/IL | Leadtrend | xxP51 |
| LD7551C | LD7551CGL | Leadtrend | xxP51C |
| NX1049 | XN1049TP | Xian-Innuovo | 49xxx |
| OB2262 | OB2262MP | On-Bright-Electronics | 62xx |
| OB2263 | OB2263MP | On-Bright-Electronics | 63xx |
| PT4201 | PT4201E23F | Powtech | 4201 |
| R7731 | R7731GE/PE | Richtek | 0Q= |
| R7731A | R7731AGE | Richtek | IDP=xx |
| SD4870 | SD4870TR | Silan Microelectronics | 4870 |
| SF1530 | SF1530LGT | SiFirst | 30xxx |
| SG5701 | SG5701TZ | System General | AAExx |
| SG6848 | SG6848T, SG6848T1, SG6848TZ1, SG6848T2 | Fairchild / ON Semi | AAHxx EAxxx |
| SG6858 | SG6858TZ | Fairchild / ON Semi | AAIxx |
| SG6859A | SG6859ATZ, SG6859ATY | Fairchild / ON Semi | AAJFxx |
| SG6859 | SG6859TZ | Fairchild / ON Semi | AAJMxx |
| SG6860 | SG6860TY | Fairchild | AAQxx |
| SP6850 | SP6850S26RG | Sporton Lab | 850xx |
| SP6853 | SP6853S26RGB, SP6853S26RG | Sporton Lab | 853xx |
| SW2263 | SW2263MP | SamWin | |
| UC3863/G | UC3863G-AG6-R | Unisonic Technologies Co | U863 U863G |
| XN1049 | XN1049, XN1049TP | Innuovo Microelectronics | 49 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.
| Name | Part Number | Fabricant | Marking |
|---|---|---|---|
| AP3105/V/L/R | AP3105KTR-G1, AP3105VKTR-G1, AP3105LKTR-G1, AP3105RKTR-G1 | Diodes Incorporated | GHN GHO GHP GHQ |
| AP3105NA/NV/NL/NR | AP3105NAKTR-G1, AP3105NVKTR-G1, AP3105NLKTR-G1, AP3105NRKTR-G1 | Diodes Incorporated | GKN GKO GKP GKQ |
| AP3125A/V/L/R | AP3125AKTR-G1, AP3125VKTR-G1, AP3125LKTR-G1, AP3125RKTR-G1 | Diodes Incorporated | GLS GLU GNB GNC |
| AP3125B | AP3125BKTR-G1 | Diodes Incorporated | GLV |
| AP3125HA/HB | AP3125HAKTR-G1, AP3125HBKTR-G1 | Diodes Incorporated | GNP GNQ |
| AP31261 | AP31261KTR-G1 | Diodes Incorporated | GPE |
| AP3127/H | AP3127KTR-G1, AP3127HKTR-G1 | Diodes Incorporated | GPH GSH |
| AP3301 | AP3301K6TR-G1 | Diodes Incorporated | GTC |
| FAN6862 | FAN6862TY | Fairchild / ON Semi | ABDxx |
| FAN6863 | FAN6863TY, FAN6863LTY, FAN6863RTY | Fairchild / ON Semi | ABRxx |
| HT2273 | HT2273TP | HOT-CHIP | 73xxx |
| LD7510/J | LD7510GL, LD7510JGL | Leadtrend | xxP10 xxP10J |
| LD7530/A | LD7530PL, LD7530GL, LD7530APL, LD7530AGL | Leadtrend | xxP30 xxxP30A |
| LD7532 | LD7532GL | Leadtrend | xxP32 |
| LD7532A | LD7532AGL | Leadtrend | xxP32A |
| LD7532H | LD7532HGL | Leadtrend | xxP32H |
| LD7533 | LD7533GL | Leadtrend | xxP33 |
| LD7536 | LD7536GL | Leadtrend | xxP36 |
| LD7536R | LD7536RGL | Leadtrend | xxP36R |
| LD7537R | LD7537RGL | Leadtrend | xxP37R |
| LD7539C GL | LD7539C GL | Leadtrend | xxP39C |
| ME8204 | ME8204M6G | MicrOne | ME8204xx |
| NCP1250 | NCP1250ASN65T1G, NCP1250BSN65T1G, NCP1250ASN100T1G, NCP1250BSN100T1G | ON Semiconductor | 25xxxx |
| NCP1251 | NCP1251ASN65T1G, NCP1251BSN65T1G, NCP1251ASN100T1G, NCP1251BSN100T1G | ON Semiconductor | 5xxxxx |
| OB2273 | OB2273MP | On-Bright-Electronics | 73xx |
| R7735 | R7735AGE, R7735HGE, R7735GGE, R7735RGE, R7735LGE | Richtek | |
| UC3873/G | UC3873-AG6-R, UC3873G-AG6-R | Unisonic Technologies | U873 U873G |
TELEFUNKEN TF-LED32S52T2S LCD TV LSC320AN09-H measuring 31.5" (80cm) diagonally in 16:9 aspect ratio. 330 cd/m² screen brightness is provided by an LED backlight. Contrast, as the ratio of maximum brightness to minimum brightness, is 5000:1. The screen technology of this TV model features LED backlighting.
The LSC320AN09-H matrix and MainBoard MSA6285-ZC01-01 software realize an HD picture quality of 1366x768 resolution in 720p (HD Ready).
The TF-LED32S52T2S comes with SMART Software and preinstalled Android OS. Internet connection can be established via Wi-Fi. Supports media formats: MP3, MPEG4, Xvid, MKV, JPEG.
The 10W (2x5W) sound system is powered by two speakers. NICAM STEREO audio processing system is used.
External interface (connection with other devices) is supported by standard inputs and outputs: antenna input (RF), AV, HDMI x2, USB x2, Ethernet (RJ-45), Wi-Fi. There is a headphone output. The digital tuner receives DVB-T, DVB-T2, DVB-C TV channels.
The power supply is used as part of the MainBoard.
Dimensions: With stand 731x481x200mm, without stand 731x433x70mm.
TV weight: 4.9kg.
Warning. The LSC320AN09-H bezel of your TELEFUNKEN TF-LED32S52T2S LED TV is an expensive and fragile part of the TV.
Avoid all impacts to the glass and pressure on the surface of the screen to avoid damage to the LED panel!
It is also not safe to get liquids on the screen. Sometimes a single drop is enough if it drips down the glass onto the cables and the television becomes unrepairable.