Philips Tv Power Supply Repair - canceling PFC circuit

[@apostolosbakaloumas8410]

To be able to identify each circuit and cancel it, means that you know what you are doing. Excellent work! Nicely done :)))

[@kriswillems5661]

The PFC makes sure there are less high frequency peak currents (than you would have when using a normal bridge rectifier only). This is necessary to comply with European standards. Another side effect is are slightly less energy losses in the circuit. The PFC circuit increases the voltage on the primary side of the transformer. Without it the transformer will need to switch with a different (wider) pulse width to get the same secondary voltage. So, the whole circuit will have more difficulties with lower supply voltages and the transfo and switching transistor or mosfet will be a bit more stressed (usually without causing too much problems). The function of the PFC is not to make the TV work on 110 and 220V. It only slightly increases the primary voltage, as it uses only a very small coil.

[@Oak690]

Yes - PFC reduces harmonics and shapes the input current to be sinusoidal.

[@danielrandall2081]

@@Oak690 yep mmhmm uh huh

[@volodumurkalunyak4651]

PFC makes sure input current is in phaze with voltage, that makes power company happy, and compensate for input voltage variations and gives ability to use narrow input range and very efficient LLC converters. Also full range PFC is there to accomodate any mains supply without having oversized primary filter capasitors.

[@IsaacOLEG]

@@volodumurkalunyak4651 Isaac OLEG il y a 1 seconde Ok so when watching the tension at the pins of the large capacitor, I am supposed to see the voltage going from 325V (DC ( I am in France) to 390 or so ? I have a CI CM6802 which is driving the pfc and the pwm , and I see none of the expected tensions at its pins. I did not find any part out of order at that time, and there is some 4/8v DC (alteranting at 1Hz +-) showing up where I should have a SB voltage and other places. WHat would be the best place to look at with oscillo and voltmeter now that I am sure the rectifier is good ? ANy idea 'at large" would help, I will look for more understanding if you can point a finger for me ;) Best regards

[@volodumurkalunyak4651]

@@IsaacOLEG if you are measuring less than rectified mains voltage (should be around 325V in EU, must be higher than RMS ac mains voltage) on a pfc capacitor, that indicates pfc circuit not just diabled, but completely broken. PFC Boost diode, PFC boost inductor, PFC switching transistor, bypass diode and inrush limiter (can be often found after diode bridge) are components, worth checking Also fuse or power input traces might be blown. If you are getting 325V, but 390V there are anouther causes for that, for example 1. Standby mode (main PFC + PWM controller is shut down, small auxillary one powers what's needed) 2. Small auxillary PWM controller is dead, so main one is not powered. 3. main (PFC+PWM) controller is blowm, PWM + PFC transistors + driver circutry, controller own filter capacitor are worth checking. 4. Short circuit somewhere at the output, so main PWM+PFC controller laches in output disabled state.

[@simeonmihaylov6123]

Of course it was a dodgy move, Sorin come on. That's why we watch every single one of your videos and we appreciate the ideas you give us. :))))

[@antonia4722]

Sorin..I think you are a bit of a genius! Ive now watched so many of your videos that when Im working on fixing equipment I find myself thinking with your accent!! You have created the best channel for education and entertainment in Electronic Repair on the internet. Thank you for all of your efforts in bringing your knowledge to us in such a way as this. Kindest regards to you Sorin :o) xx

[@graffygerry]

Finishing electronics engineering this year, binge watching your videos at the bus before going to class. Very entertaining videos, keep it up!

[@beautyzonemachinery]

Buna seara ! Va urmaresc postarile cu placere si mult interes inca de la primele postari( lucrez in aceasi bransa -repar aparatura medicala si de infrumusetare dar si laptop-uri , tv, etc),dar urmarind acest videoclip, am constatat cu si mai mare placere -faptul ca sunteti roman, de aceea vreau sa va felicit pentru filmuletele cu un continut extrem de valoros pentru cei pasionati de electronica si tot ce implica repararea aparaturii electronice ! Profit de aceasta ocazie sa va urez multa sanatate , fericire si indeplinirea tuturor dorintelor! Multumim pentru continutul video extrem de bine documentat , La Multi Ani dvs si intregii familii!!!

[@minaliviu3287]

Salutari domnul Sorin am vazut un film american mai demult MacGyver acum ca mi sa stricat tv si un roman care este la fel ca personajul din film ma ajutat cu informatii puse pe youtube este super tare multumesc nici macar nu sint de meserie imi place sa vad ce are cind se strica ceva in casa

[@kahlid-ataya]

The most tow things i like in your videos is your accent and that your videos isn't edited

[@bblod4896]

Engineer: "How can we make repair of this board a bit more difficult? I know, lets hide the screw behind the transformer" Brilliant!

[@thembaningwenya1620]

Thanks Mr Sorin for making electronics to be easier , your experience is helping us.

[@AnonymousRepair]

PFC stands for power factor correction , is to make the tv more efficient in power usage, not for 120v or 240v , the PFC use the coil to bring the current and voltage in to sync giving a power factor of 1. switch mode power supply can have bad power factor witch use more power then needs

[@Adventcha]

Great stuff Sorin, you have taught me a lot, Kev from New Zealand

[@therealspixycat]

Very very interesting you telling how you analyse and attack a fully unknown board. Many thanks for sharing!!!

[@najmuddinharniswala7265]

Indeed very informative.. I have repaired many of these.. since I was running a 3rd Party Service Centre for Philip's...

[@kjuirteerdserty9618]

Its so beauriful when a blown capacitor shows up....

[@chrisblank9090]

mr sorin, the resistor(s) connected to the positive side of the capacitor going to the pwm controller chip of the pfc is for pfc voltage output regulation. the vcc of that pwm chip is switched on and off by the mainboard via an opto coupler and a bipolar/darlington transistor/fet. that vcc comes from the standby smps transformer mostly 15 volts

[@sergelavallee7331]

So???

[@chrisblank9090]

Serge Lavallee so? la? ti? do?

[@sergelavallee7331]

@@chrisblank9090 We don't need an electronic lesson here. Good for you if you know all that lol. The important thing is to FIX THE THING LOL!

[@chrisblank9090]

Serge Lavallee and are you speaking for all the people who's watching or watched this video? I never mentioned anything ofensive or rubbish right? what's with the trigger issue?

[@sergelavallee7331]

@@chrisblank9090 Just forget about it ok? Thank's Regards. That was a mistake.

[@olyforis1103]

Super interesant, ma bucur ca face cineva din romania asta :D

[@bilalbozkurt4309]

the best electronic chanel. like working together. hi from turkey

[@nesport3751]

To kind and in real time no edits made, Thanks and i love your videos and i learn alot from them. :-)

[@hotlava2222]

How about a video on how to test components... Especially mosfets and transistors

[@ibrahimhasan980]

Nice one. I think we need some basic courses of TV main circuits to be able identify why are they exist .may you Mr. Sorin give us these kind of courses about TVs parts physiology :)

[@davutozturk3348]

I suprize that the TV works whitout the mosfet. Thanks again. I love your style.

[@ozosman3234]

Hi Sorin. Iv'e recently come across your channel just by chance, and i found it to be really informative and also fun. I am 68 years old and have started to get interested in electronics and computers. I don't know anything about computers, laptops, tablets or mobilr phones, but would like to learn about how these pieces of equipment work. I enjoyed looking at your beginner classes and wondered if yoy could do one on the 'basic' building blocks of how computers function. For example you mention terms such as the bios, super i.o., digitizer screen. I am sure these are known by people familiar with computers, but to people like me, they are impssible to see where they fit in a computer or what they do. My apologies for such a long letter. All the best to you and your family from " sunny Devon".

[@electronicsrepairschool]

Hi, thank you for your comment. Video about how computers works ... thats not a bad idea at all, ok i will try to find some time for a video then. Great to see ppl interested in electronics!

[@robsmits695]

Your the best on KZbin the Samsung 55 inch I fixed whit your help

[@tinkmarshino]

it is good to know that a quick cheap fix can be applied to something as ratty as an old tv.. What is the cause of this problem? and by bypassing the booster did you also eliminate the original problem? As for dodgy.. the customer paid you to do it down and dirty.. get it working and do not spend time or money.. and that is what you did.. Just as you were told (and paid) to do.. well done!

[@radiotriggered2096]

We love you Sorin, we do. We love you Sorin, we do. We love you Sorin, we do. Ooooooohhhh!!!! Sorin we love you!!!

[@roseelectronics4582]

Nice song!

[@5pr1nk57]

PFC is used to make the TV power supply more energy efficient due to the amount of inductors or inductive load in the circuit. It's an issue in a big factory with large motors and hundreds of stip light ballests but not the end of the world in a small LCD TV though I would still repair, unless the customer was an arse! 😅 Where you based, UK? My friend has a mobile repair shop in my town just outside London, I do all there compont level repairs of consumer electronics and am an electrician also :)

[@vernonbosshard9317]

So you can remove the FET and disable the PFC circuit and the Tv will work? I removed the shorted FET on mine and the dead short is gone, but I'm afraid to put it back in the TV to test it further, I got this TV DOA. I can bench power board first but...I'm like will this work for a test in the TV??? I'm not a gambler.

[@lambsy2278]

Nice work - the customer is always right.

[@ukaszsl.6242]

Hi, i need to repair or just remove PCF in Samsung BN44-00473 B . Can you help me what parts I need to remove ?

[@therealspixycat]

Any idea why the samsung is not charging or randomly charging rebooting? I have a s7 with the same issue.

[@vladuzz7]

asteptam si clipuri in romana domnule Sorin :)

[@jeffrozanski9414]

Hows that getting power with no wire injection?win u testing?

[@davidederosi6068]

I love this videos! You are simply great. The best part is when you get away from sparks or exploding compnents and let the dangerous part to your assistant 😂🤣🍷

[@davidederosi6068]

I have a board (05ta071b power boaed for lcd) wich fuse is gone. Replaced like yours and gone again. The 4 diode bridge is ok i suppose cause I cheked it in continuity mode and it seems ok. When performing a 230V check with a spare fuse I see sparks and bangs and a diode exploded someahere near a big transofmer. The transformer itself has the input part (4 pin) ok but the out ( 8 pin) are all of them shirted to ground. Removing the transformer partially solved the short but I still think I'm not in the right path. So I surrender, for now. Ordered a new(used) part. Anyway I would like to learn from this board. What do you suggest?

[@reacey]

So did you bypass the fet or just remove it I don't understand

[@richardhemingway6084]

I don't either. Could do with a quick sketch of a diagram to explain.

[@richardhemingway6084]

I found this. It explains the PFC circuit, kzbin.info/www/bejne/iZjEqZpqe754hac So looks like just removing the MOSFET will do it.

[@reacey]

@@richardhemingway6084 thanks Richard

[@ninshowplays52]

Watching from philippines here..😊

[@ketmokserasine8468]

Its friday.. thanks a lot sir for sharing your knowledge...

[@Amraks]

I knew that mosfet was going to be shorted after you found that cap. Seen some similar ones.

[@ziggy_makes_videos]

Hi master, nice to see your video again

[@billvouronikos9441]

by far the best teacher love ya!!!

[@jamesmdeluca]

Geetings from California USA: Former associate from Romania is now back home. Anton Cretu in case you know him.

[@chrisblank9090]

that pfc circuitry lessens the power consumption of the unit and adds more to the repair cost. and adds breakdown frequency.. the money you'll save in power consumption will be just a fraction of the additional repair cost. 380 to 400 volts dc is extremely stressful to power semiconductors. no pfc, a bit more power eaten up, but the power supply will last longer

[@volodumurkalunyak4651]

Pfc takes care or lawmakers making power factor regulations, it does not save power directly. It can be used to save power, if follower by LLC converter. LLC converters have very limited input range, but very high efficiency, so PFC boosts any mains to 380V DC +- 20V, excatly what LLC converters need

[@Damjanhd]

I have repaired once switch power, I checked all and replace mosfet and some trensistor, but still didn't worked, than I buy the same one and measure also resistors and find out 3 resistors are broken with wrong resistance it was not 0 but totally wrong.

[@kolo1367]

Hello, what's your multimeter?

[@albertosamson820]

now I heard your native language... fantastic, and I wonder your English sounds like Russian. thanks for the video anyway, your a great teacher.

[@Mattia_22]

Great job. Greetings from italy Mr Sorin thanks for the videos🙏🙏😁

[@Waasil]

Thank you very much for the good video.

[@SanelKeys]

Did you mean snubber capacitor? If it's snubber, then it reduces switching stress on MOSFET.

[@transformateur9969]

thank you Sorin, good weekend

[@AkiraReyna]

This is new one...new ideas and techniques..thank you sir

[@swake0019]

The multimeter is measuring voltage... it is not measuring resistance. Not possible to measure a short like this unless the board is powered. I guess you'll notice it by the end of the video but I can't wait posting this :-D

[@IsaacOLEG]

yes ? i did not see where the short did show up on the displays

[@vdtran69]

Well explained how to troubleshoot the problem

[@giorgostexnikos6976]

thenks professor for tthis video allways we lern from you.

[@joaopires2985]

perform same on my tv same model and same problem .. fuse busted and capacitor. remove all bad part new fuse. now i have power but tv dosent start . flash led wen power starts . for me dident work . i will try to replace all bad parts and start again .thanks for lesson much appreciated

[@jameswiz]

Can you please do a video, and explain how 12v car battery Series Chargers work? I have one that can accept upto 10 batteries. 4v, 6v, 8v, 12v it doesn't care. It has an "On/Off" switch and a big knob that i can turn... We charge everythibg around 2amps... So depending on how many batteries are hooked up, I just turn the knob until the meter shows 2amps. Then everything chargers perfectly. The voltage varies and amperage varies. How the hell does this circuit work?? And perhaps build a bench unit to demonstrate it?? Please??

[@LIONJCOMPUTERSOLUTIONS]

please teach us how to remove power protection on a linear power supply....... please please please

[@2good4trash63]

I have awish for a futere video!!! In my case i have a Laptop where the Control IC(RT6575) for the 3.3V and the 5V PSU shuts of the 3.3V Powerrail! There is no shortt on the Mainboard and i dont find out why this happens!!! Maybe u have a Mainboard with similar problems!!! The next thing i will try on mine is to flash the BIOS Chip with new Software maybe this will help! But it would be great to see how u handle this kind of problems!!! Greetings Chris

[@sonicpk100]

10:10 is balkan or daco?

[@MindYourBusiness1970]

Finally Friday :)

[@chamaraweerasinghe5836]

this sunday will you start making switching power supply sorin sir

[@geoepi321975]

If you want to learn check donkey learning chanel also

[@GeorgeGeorge-xj2bc]

This board suffers mainly from the high voltage transformer that drives the ccfl and there is no replacement nowhere in the planet for the trafo or the entire board and secondly the tv suffers from failure of the cof's on the screen glass due to the excessive heating coming from the fluorescent lamps.So this series lcd tv has already ended its life circle and it was limited only between 4-5 years and no more.

[@loizostheochari1509]

Sorin you will need a right angle phillips screwdriver. Why not replace the mosfet with a substitute mosfet.

[@droidfane]

Felicitări!

[@jaimecosta2966]

Excelente job

[@MindYourBusiness1970]

It happened because he didn't replace with a proper calibrated one

[@sonicpk100]

k series mosfet with diode bridge pfc nice bypass

[@sanjubtn78]

it will not work 110 volt area , without the booster circuit .

[@yuanho2883]

is that a Fluke multimeter? nice!

[@electronic7979]

👍 I like it.👍

[@richardcranium5839]

with all the newer electronics these days i dont understand why we dont have a transformer and 12v dc circuit outlets running in our houses. have the 110 ac or 220 ac for your big loads hard wired and everything else run off 12v dc so much safer and would cut down all the step down rectifying circuits we use. we are still in the past trying to keep up with the future

[@MindYourBusiness1970]

Planned obsolescence

[@DimitriPappas]

12V DC is difficult to distribute, even in a small household, because of the voltage drop under load requiring thicker cables for the transmission. high voltage AC works well with thinner cables. But yes, it would still be nice if appliances were 12V rated and the consumer could choose a suitable 12V power supply of capable amperage. If the power supply fails, you just replace it. If the TV fails, you can know its the TV and not the power supply. But manufacturers know that most people have an AC outlet nearby, so it makes more sense to mass-produce AC-rated appliances. They also make more sales because if a power supply fails, many users just go out and buy a whole new TV. Just one of those things! But nothing is stopping us as tech enthusiasts from installing our own "home 12V rail" in each room and wiring up pretty much whatever we want to that, including lights etc. I know I plan to do that for my home in the near future as it is more efficient especially in a blackout as then you don't need an inverter to inefficiently step up the voltage from your batteries only to step it down again with an SMPS etc

[@richardcranium5839]

@@DimitriPappas my friends house has a similar set up his dad did in the 60's . got plans from a magazine and did all his lighting dc vow volts. so its not a new concept. i think you'll find architects doing this in high end first and it will slowly grow from there.

[@zx8401ztv]

Some tv sets won't operate without the boost circuit, i think the main capacitor voltage is monitored, if not above 320 volts then it won't power up. I had one like that, once the pfc was good and 400+ volts was there, it powered up fine :-D Bad capacitors :-(

[@chrisblank9090]

zx8401ztv theres an optocoupler or a pfc detect pin for that. it can be modified

[@tington874]

Hello, i think it would be a good idea to order a hand pump, only a few £ it is very useful for small tasks, no need to invest in electric pump for your activity anyway ....

[@mikem4432]

The customer probably does not want to spend fixing the old one if it costs more than it is worth.. dodgy, or economical? sure Sorin could fix it all up, but the customer does not want to pay for it.. at least he got it working again.. which should make the customer happy, and that is what keeps people coming back. However, I would of put a new fuse to replace the blown fuse once it was working with a proper fuse, just to be safe.

[@wisher21uk]

Using those military calibrated fuses

[@captainjim1010]

"Your customer can't go with this TV to America" AHAHAHA

[@technologiedz]

best video master

[@armandosassi7245]

Quanto costa quella scheda philips

[@mre3820]

I wanted to see Christian jump 😁🤣

[@FerdAboubakrOnline]

Hahahaha manufacturers should have a look at your work haha I am sure they will cut a lot of expenses and minimize the number of components used

[@0dium.]

sure, and firemen will have more calls :)

[@leerzeichen1910]

hi! knows someone where the shop exactly is located? the adress will be nice. thx!

[@smdelectronics6485]

Sir.,can you shout out me,in next video.. from Philippines 🤘🙏

[@dragan059]

PFC decreasing reactive power and TV uses less power. Less power means less money to pay every month.

[@armandosassi7245]

Io la sto cercando come devo fare del 42 pollici

[@kadmaster]

Hello Sorin!...Come to besiktas and I love tv repairs...

[@WeFixTvs]

Sorry to say this but its is not a such good idea to return this tv to customer without PFC, If will be small drop voltage in the main socket it may not start backlight. Im not blaming you just know from experience this tv may return to you,

[@protonx80]

it wont be returned ... everything is ok ... it will just draw a little more power thats all

[@MrRvdbeek]

You are still the best I thank you 🙏 and you did switch the camera and still working 🎙 and it’s funny yes it is 😂

[@MeFixingEverything]

You get what you paid for.

[@danielsaturnino5715]

If it works for cheap and the guy doesnt want to pay enough, then its good enough.

[@SmoothJaZzFusion]

I'm here just to hear the word Thermister lol, I'm kidding

[@irzumkhan412]

like ,share, subscribe.......definately Mr Sorin great great great///////

[@weerobot]

More Cool videos...

[@cesaru3619]

what? no smoke of gods rosin?

[@studenteducationlife9139]

wow

[@sugathjayathissa6662]

T.R..NUMBER.ERASED....PLESE...WHAT.. UMBER?

[@memorywarrior8752]

Apparently Christian is known as Chris Test Dummy.

[@intrax2tv]

Please replace components to make customer happy i.o. dodgy jobs 😬 !

[@chrisblank9090]

he did the customer a favor. power supply circuitry is safer without the pfc

[@intrax2tv]

Chris Blank haha your education from somalia ?

[@chrisblank9090]

intrax2tv and maybe you have no idea about the work sorin did right,

[@intrax2tv]

Chris Blank you seem a terrible idiot, customer expect nice job, replace parts, parts cost is very low... just plain lazyness!

[@intrax2tv]

Paul Sanderson these parts cost peanuts, check price before comment !

[@dave-ux1iu]

so funny thanks

[@CASHSEC]

Too disjointed. But you know more than me.

[@cotto887]

you are too lazy too replace the fuse.once the short was fixed

[@DallasAya]

Hot Glue Who Knew Ha Ha Ha.......Done that one b4.........on a MaggotBox