Monday, 9 November 2020

REPAIRING / SERVICING TV PHILIPS 32PHS4012


 Technical description and composition of the PHILIPS 32PHS4012 TV, panel type and modules used. The composition of the modules.
PHILIPS LED
Model: 32PHS4012 / 12
Chassis / Version: KTS17.1E LA
Panel: LC320DXY (SJ) (A7) // K320WD82
T-CON: 6871L-5218AG
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.MS3463S.PB755
IC MainBoard: CPU: MSD3463GSA, EEPROM: 25Q64, AUDIO: OB6220RVPA
Tuner: CDT-9NT372-RF01
Specifications 32PHS4012
PHILIPS 32PHS4012
General recommendations for TV LCD LED repair
Possible malfunctions
- PHILIPS 32PHS4012 does not turn on, does not respond to buttons and the remote control, the indicators on the front panel do not light or flash.
In such cases, the main power source may be faulty - the AC / DC converter of the mains voltage, which is combined with the MainBoard TP.MS3463S.PB755. It is then necessary to measure its output voltages and, in their absence, the power switches (TO-252) and the rectifier diodes of the converters should be checked for the probability of a short circuit.
In case of any breakdowns in the secondary circuits, the converter can operate in an emergency mode of a short circuit, and in the event of a short circuit in the power elements of the primary circuit, the mains fuse or the current sensor in the source of the key is often cut off.
Breakdown of Mos-Fet keys used in switching power supplies is often caused by malfunctions of other elements, for example, in the power supply circuit of a PWM controller, in frequency setting or damper circuits, as well as in negative feedback stabilization. PWM microcircuits (PWM) PWM SOT23-6 are usually checked by replacing them with new ones, or known to be working properly.
- There is no picture, but there is sound and all other TV functions are working. The image sometimes appears for a second immediately after switching on and disappears.
The malfunction in most of such cases is found in the nodes and elements of the LED panel backlighting. The reason for this may be an open circuit in the LED circuit, or a problem in stabilizing their power supply.
It is impossible to identify an open circuit in the LED line without disassembling the panel with a simple multimeter. The LEDs are connected in series and a voltage of several tens of volts is required to open their junctions. Ideally, a current source is suitable for such purposes. You can open the panel and check each LED separately. Usually, Chinese multimeters lightly light one 3-volt LED if you connect the probes to it in the forward direction (red probe to the anode, black to the cathode). For dual 6-volt LEDs, the PN junction of its emergency zener diode can serve as an indicator of LED health. In the event of a malfunction of the LED, its zener diode will either be cut off or pierced in the K / Z.


- The indicator blinks or is on constantly, the TV does not turn on, does not respond to the remote control.
Repair or diagnostics of the TP.MS3463S.PB755 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). Complicated MB (SSB) repair is possible only in the conditions of a service center with the necessary equipment. Checking or replacing elements CPU: MSD3463GSA, EEPROM: 25Q64, AUDIO: OB6220RVPA requires the necessary training and professional skills to repair modules at the component level. Problems associated with the use of BGA soldering technologies can sometimes be diagnosed by the warm-up method.
If there is no reception of TV channels, but the TV is working properly from external devices, first of all, you need to check the supply voltage of the CDT-9NT372-RF01 tuner and update the software. I2C communication pulses must be monitored with an oscilloscope.


Owners and users of the PHILIPS 32PHS4012 TV should remember that self-repair without special knowledge, skills and qualifications can be fraught with negative consequences that can lead to complete non-repairability of the device!

 

 DOWNLOAD SCHEMATIC DIAGRAM  / SERVICE MANUAL   ------------------>  PHILIPS 32PHS4012 Chassis KTS17.1E LA

 

The appearance of the MainBoard TP.MS3463S.PB755 is shown in the figure below:



TP.MS3463S.PB755
The main features of the PHILIPS 32PHS4012 device:
The matrix (LED panel) LC320DXY (SJ) (A7) or K320WD82 is installed.
Matrix control uses the Timing Controller (T-CON) 6871L-5218AG.
To power the backlight LEDs, a converter combined with the TP.MS3463S.PB755 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 SOT23-6 PWM microcircuits and TO-252 type power switches.
MainBoard - the main board (motherboard) is a TP.MS3463S.PB755 module, using CPU chips: MSD3463GSA, EEPROM: 25Q64, AUDIO: OB6220RVPA and others.
The CDT-9NT372-RF01 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

 

 

PHILIPS 32PHS4012 TV with LCD LC320DXY, diagonal size 31.5 "(80 cm) 16: 9. The required screen brightness of 250 cd / m² is provided by LED backlighting. The LCD panel is implemented with direct LED backlighting.
The LC320DXY sensor and MainBoard TP.MS3463S.PB755 software provide high quality HD viewing at a resolution of 1366x768 pixels in 720p (HD Ready). Supported media file formats: MP3, WMA, MPEG4, HEVC (H.265), MKV, JPEG.
Speaker power 16 W (2x8 W) is provided by two speakers. Uses NICAM stereo processing system and Sound Surround function.
External interface (communication with other devices) is supported by standard input and output connectors: antenna input (RF), AV, component, HDMI x2, MHL, USB. A headphone output is provided. The digital tuner is capable of receiving television channels in the DVB-T, DVB-T2, DVB-C, DVB-S, DVB-S2 standards.
The TV uses a power supply unit as part of the MainBoard.
Dimensions: with stand 732x492x183 mm, without stand 732x432x76 mm.
TV weight: with stand: 3.9 kg, without stand: 3.8 kg.
Attention! Panel LC320DXY (SJ) (A7) LED-TV PHILIPS 32PHS4012 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.

Instructions and updates --------------------------> Documentation: Declaration of Conformity PDF file, 282.8 kB, published September 7, 2017
User manual PDF file, 939.1 kB, published November 6, 2018
Brochure Version: 11.5.1, PDF file, 443.9 kB, published February 20, 2020
Product Fiche PDF file, 112.2 kB, published October 22, 2018
Quick start guide PDF file, 1.6 MB, published October 22, 2018
The files can be downloaded from the manufacturer's website for model 32PHS4012 / 12.