Technical description and composition of the SKYLINE 40LST5970 TV, panel type and modules used. The composition of the modules.SKYLINE LED
Model: 40LST5970
Chassis / Version: TP.MT5510S.PB803
Panel: HK400LEDM-JH28H
LED backlight: 06-40F1-3X7-755X14 261501008260
LED driver (backlight): integrated into MainBoard
PWM LED driver: 8 pin
MOSFET LED driver: TO-252
Power Supply (PSU): integrated into MainBoard
PWM Power: PWM SOT23-6
MOSFET Power: TO-252
MainBoard: TP.MT5510S.PB803
IC MainBoard: CPU, eMMC, AUDIO, DC / DC
Tuner: NoName
Specifications 40LST5970
SKYLINE 40LST5970
General recommendations for TV LCD LED repair
Possible malfunctions
- The SKYLINE 40LST5970 TV does not turn on, does not respond to the remote control and control panel buttons, the indicators do not light up or flash.
In this case, first of all, you should check the operability of the main power source - the AC / DC voltage converter, all the elements of which are located on the MainBoard TP.MT5510S.PB803. Then we recommend measuring its output voltages and, in their absence, you should check the serviceability of the power switches (TO-252) and rectifier diodes of the converters 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 with a short circuit in the power elements of the primary circuit, the mains fuse and / or current sensor in the source of the key usually breaks off.
Breakdown of power switches (MosFet) in switching sources is sometimes caused by malfunctions of other circuit elements, for example, in the circuits supplying the PWM controller, frequency setting or damper, as well as in the circuits of Negative Feedback (OOS) stabilization. PWM regulators (PWM) PWM SOT23-6, if they have no visible damage to the case and an open short circuit between the pins, are usually checked by replacing.
- No picture, sound, all other TV functions work. When turned on, the image may sometimes appear for a second.
Usually, in such cases, there is no backlighting of the LED panel (matrix). The reason for this may be an open circuit in the LED circuit, or a problem in stabilizing their power supply.
To check the health of the LED circuit, it is better to use a current source with a maximum voltage of 200V. We do not recommend using any voltage sources for this purpose. You can check each LED separately with a simple Chinese multimeter (powered by 9 volts) in the P-N transition test mode. If you connect the red probe of the multimeter to the anode of the LED, and the black one to its cathode, then the 3-volt LED will light up slightly, and in the opposite direction you can detect the transition of the emergency zener diode. The serviceability of the PN junction of the Zener diode indirectly indicates the serviceability of the LED-a
- The indicator on the front panel blinks, the TV does not turn on in operating mode, does not respond to the remote control.
Repair or diagnostics of the TP.MT5510S.PB803 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). In cases of attempts to repair the MB (SSB) board, it is necessary to check the serviceability of its elements - CPU, eMMC, AUDIO, DC / DC, which may require replacement with new ones. If a BGA processor is installed, there is a possibility of a violation of the soldering of the contacts of its pins with the board (indicated by warming up).
Before changing the tuner NoName, if it is not possible to tune to television channels, you should make sure that there are supply voltages, which must be measured at the corresponding terminals of the tuner and check the software for correctness. The pulses of data exchange between the tuner and the processor can be monitored with an oscilloscope
Attention! Users and owners of 40LST5970 TVs who do not have the appropriate qualifications, knowledge and experience are strongly discouraged from trying to repair themselves in order to avoid negative consequences that can lead to the complete non-repairability of the device.
Additional MainBoard Repair
The appearance of the MainBoard TP.MT5510S.PB803 is shown in the figure below:
TP.MT5510S.PB803
The main features of the SKYLINE 40LST5970 device:
Installed matrix (LED panel) HK400LEDM-JH28H.
To power the backlight LEDs, a converter combined with the TP.MT5510S.PB803 main board is used, controlled by an 8 pin PWM controller. TO-252 switches are used as power elements of the LED driver.
The power module is combined with the MainBoard and is made according to the AC / DC flyback voltage converter using PWM SOT23-6 microcircuits and TO-252 power switches.
MainBoard - the main board (motherboard) is a TP.MT5510S.PB803 module using CPU, eMMC, AUDIO, DC / DC chips and others.
Tuner NoName 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.
| 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 |
SKYLINE 40LST5970 TV with LCD display HK400LEDM-JH28H, diagonal 40 "(102 cm) in 16: 9 format. The required screen brightness of 240 cd / m² is provided by LED backlighting. Dynamic contrast ratio of 80000: 1 is achieved by special LED control. The LCD-panel of the TV is implemented with direct backlighting with LED back-mounted - Direct LED.
There is a convenient function of recording TV programs on a USB-drive with subsequent viewing at another time (TimeShift).
The HK400LEDM-JH28H LCD panel and TP.MT5510S.PB803 main board software provide viewing of broadcasts and movies in high quality HD at a resolution of 1920x1080 pixels in graphics resolution at 1080p (Full HD).
40LST5970 TV has built-in SMART software and pre-installed Android Operating System. Internet connection can be made via Wi-Fi wireless connection. Supported media file formats: MP3, WMA, MPEG4, Xvid, MKV, JPEG.
Speaker power 20 W (2x10 W) is provided by two speakers. Uses NICAM stereo signal processing system and Sound Surround function.
The external interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, component, VGA, HDMI 1.4 x3, USB x2, Ethernet (RJ-45), Wi-Fi. A headphone output is provided.
The digital tuner is capable of receiving television channels in the DVB-T MPEG4, DVB-C, DVB-T2 standards.
The power consumed by the TV operating in mains mode is 74 W.
Dimensions: with stand 910x567x190 mm, without stand 910x527x80 mm.
TV weight: with stand: 7.4 kg, without stand: 7.2 kg.
Attention! The HK400LEDM-JH28H panel of the SKYLINE 40LST5970 LED TV is an expensive and unreliable element.
Do not allow any impacts 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 non-repairable.
