12V 2A LED Power Supply test - with schematic

Подписаться 230 тыс.

Просмотров 730 тыс.

50% 1

In this video I test a Chinese 12V "2A" switching power supply designed for LEDs, CCTV, routers, etc. It cost me only $ 1.80 including shipping. The actual current capability is about 0.5A and the safety is quite questionable. It's a classic 2-transistor switching power supply with an optocoupler, but it's quite underrated, has poor mains isolation and misses basic safety features like a fuse. It may be dangerous and it can only supply 1/4 of its rated current.
You can support me on Patreon:
/ diodegonewild
My Instagram:
/ savage_danyk

Наука

Опубликовано:

25 окт 2017

Ссылка:

Скачать:

Готовим ссылку...

Добавить в:

Мой плейлист

Посмотреть позже

Комментарии : 309

@deweywsu 6 лет назад

Great teardown and analysis! I really appreciate your videos because you not only break things like this open, you take the time to reverse engineer them, actually draw a schematic AND explain it. That's quite impressive. You are helping more people than you realize. Thank you for making your videos!

@DiodeGoneWild 6 лет назад

Thanks, I will keep making such videos :).

@kulanchandrasekaran4462 6 лет назад

Great breakdown and analysis. Your intelligence and insight are greatly appreciated. The way you elongate the syllables on some of the words adds to the general air of wit and sarcasm as you gradually break down the 2 Ampère myth of this device. Keep up the good work!

@electronicshelpcare 5 лет назад

Great video as always .Keep the good work sir .You are the best teacher .I have learned a lot from you 😁

@hkchandana Год назад

You are a very good teacher. Few years ago I had a hard time trying to understand how this type of power supply works. I think it is also called 'ringing choke converter'. Thank you very much.

@RipVanWinkle_Nature_Discovery 6 лет назад

Thank you for all your hard work on this. When you started the tear down, you mentioned that although the P/S was labeled as being rated at 2A, it actually was only able to supply 0.5A. As you went through the tear down, I kept waiting for your conclusion to tell us what component(s) should probably have been changed, to make it a true 2A P/S. I'm not complaining at all, just saying. Anyway thanks for this and I liked how you explain the circuitry. Thumbs up!

@josephe3697 6 лет назад

Very good and clear explanation of how the circuit functions.

@fernsgilbert 4 года назад

good insight. also Like the way how you opened the case its always a headache for me.

@medvidekkrupicka1404 6 лет назад

Na mě udělalo opravdový dojem, jak jste bravurně odizoloval kabel kombinačkama. Respekt!

@DiodeGoneWild 6 лет назад

No jo, to jsou léta praxe :D

@user-mw1tn8me5z 6 лет назад

yaayyy a new video

@vkutuz 6 лет назад

Thanks for the video, Dan. I had a similar power supply and I could not understand why my photo frame didn’t work. Checking your video and trying to prove the same on my power supply I found that at 10ohms resistor my voltage was only 2.8V, at 5ohms it turned off, at 20ohms my resistors went smoke :) I used 1/4W resistors which are probably too small wattage for this setup.

@jasonjordan5391 6 лет назад

Awesome video very detailed look forward to seeing more👍👍

@himanshunegi5831 4 года назад

This was really one of the best presentation. I've seen 👍👍👍✌️

@salsepulveda494 6 лет назад

A great video! A good one. I just purchased two of these and I really need 2 Amps. They are currently in transit to me.

@bizkip8811 3 года назад

I like the way you explain. Plain comical and just nice

@randyginden3852 6 лет назад

You sir are a total badass! Great video!

@josephturner1513 5 лет назад

Great explanation thank you! Enjoyed the presentation tremendously.

@theworldaccordingtome6448 6 лет назад

Hi, I really like how you describe the circuit operation in these type of videos. It might be nice if you could also show actual waveforms on a scope at the various points as you describe how the circuit operates. Cheers!

@brahimabdelsadek9534 3 года назад

Nice video as usual.you re a genius man.thanks for teaching us

@pascalphase2556 6 лет назад

Lot of knowledge, very impressive...bravo !

@vinayakasyamprasad9790 Год назад

Very good explanation and analysis, thank you

@Creativity_DIY 6 лет назад

Like it ur clear check n testing...good learning.

@blabla33333 6 лет назад

i have one and opened it. there were cables that looked burned but not connted to anything.

@NNNILabs 6 лет назад

I've used a similar transformer to make a 40W flyback. It worked, but took a lot of optimization. It goes to show 24W is possible, but the designer hasn't seemed to realise that!

@kensmith5694 6 лет назад

NNNI Yes, the trick is to go up in frequency. The amount of energy you can store in the core times the frequency is the power. If you are making stuff for a narrow mains voltage range, it is even easier.

@DeddyM75 3 года назад

Very good explanation, I understand so much. Good job!! Thank!!

@dientuhandmade9412 6 лет назад

Thank you very much for your explaining

@MrWasim100100 4 года назад

nice video i like the way you opened the case :)

@odedineros1122 4 года назад

because the adaptor is very chinese 😂😂😂

@21thTek Год назад

you are a winner, best of the best !!

@creativelife4453 6 лет назад

so cool ,i like this test

@randomdosesofconnor3756 2 года назад

Thank you. You just saved me from frying up a valuable piece of electronics, had it not been for this video, it would have costed me $30 to replace!

@user-nh3xd3wp5h 4 года назад

i need this, really clearly explain, thank master

@Adamjrfamily 6 лет назад

Yes bro..you are amazing.keep it up with more helpful video.

@antraciet 6 лет назад

Thank you for this video. I got one (didn't used it yet), sort of a regulated one, with lots of adapters, that is why i bought it. From 12 to 24 volts and 5 A,...Maybe i need to test it before i use it for something.

@binarybox.binarybox 5 лет назад

Another great video, thanks. The psu is dangerous and not designed for 2 amps output. I would bin it ...maybe save the case. I have some power resistors for checking the current in power supplies and they are a quick way to test whether the unit is up to spec or indeed working.

@jesterraj 3 года назад

would have like to see some waveforms at the diff stages...great video!

@migsvensurfing6310 6 лет назад

"This looks like a chinese board" 😂👍

@tysesty 6 лет назад

Mr Diode, jak muzu udelat 1 mode driver from 5 mode driver. Thank you. Vlad

@magenrichard6468 6 лет назад

Very helpful ur tear down,

@kensmith5694 6 лет назад

At 6:26 The main transistor generally stays on until the 40 Ohms in the emitter has enough drop to turn on the other transistor. The 10nF should be big enough that this happens before the capacitor charges too far. The input side capacitor need not be big if the output side one is fairly large. Nobody is going to notice a bit of ripple in the output if the amplitude is smallish. If I was going to use something like this, I would add a fusible resistor on the mains input to restrict the inrush and protect against shorts.

@makeinheaven 6 лет назад

This video is a GREAT LESSON!!!. Thank you very much for this video. Every year i try to make a smps from 220v to down. And i fail every each year. Please make a video about very basic, usable smps with psu transformer.

@DiodeGoneWild 6 лет назад

You can for example try a very simple SMPS with a high integration chip. Something like this: danyk.cz/impulz4_en.html Or you can try a single transistor power supply like this: danyk.cz/iz_odv_en.html Maybe I will make a video how to build a simple SMPS one day....

@bhavikshah5016 3 года назад

Great stuff.. you are super entertaining too..

@nara49veera12 6 лет назад

Good and illustrative video. Thanks. I too had ordered such poor quality power supply based on spec.

@glauciapoubel135 6 лет назад

Olá, sou do Brasil e preciso de um adaptador igual a este com esta especificação. Como faço para comprar?

@hevenko 5 лет назад

Just yesterday i tried to switch on my ceiling led lamp (with intensity regulation and ir remote). Accidentally i didn't flip the switch all the way. The lamp flickered and now it is deat, transformer buzzes but there is no output. Would you be so king and help me with repair?

@MOHAMMED_1000 5 лет назад

Good job

@emmanuelb.8723 5 лет назад

Hi, how do determine how the transformer is wound to put the dots on the schematic?

@ajithkumar-ff8ey 6 лет назад

Thank you very much,Your explanation is amazing,please upload working of 12volt 400watts Chinese power supply using ic ka7500

@ebraamnageh435 5 лет назад

in the adapter when the green led lights steadily what does that mean ??? when the green led is kept flashing what does that mean?

@kerrydaddy2501 4 года назад

Very helpful thank you very much.

@necoisidois7570 6 лет назад

You are awesome..

@bierzoelite8875 5 лет назад

nice one good diagram explaination

@mrbrynh 4 года назад

I like the way you said "ARE YOU KIDDING GUYS? THAT'S RUBBISH!" its cool!

@satansoft 6 лет назад

Is the emitter on the optocoupler directly connected to the base of the 2SC945 transistor ? Does it not have current limitation?

@mrls5533 6 лет назад

Hello, Can you please help me with the circuit or youtube video for 12V 2A from 220+Volts ? How to approach that? Thank you :)

@omarcusihuaman4261 5 лет назад

Can you do a project for build your own smps power suply using scrap from broken psu?

@northstar802 4 года назад

@DiodeGonewild, i have made all circuit as you mentioned in above video. At no load, there is fixed 12V. But when i am applying load ( 12 Volt relay), transistor 13003 heats up and burning within 5 seconds. I have replaced three transistors. Can you help me in this regard that why it is happening?

@Veer-ss6et 5 лет назад

How to differentiate between an inductor and resistor in a circuit like this

@Bianchi77 2 года назад

Like it, thanks for sharing :)

@omarcusihuaman4261 6 лет назад

nice vid. it is posible to modify that circuit in order to make it safer? can you do a video about that? or maybe can you do a project of making a 12v 2A smps PSU using parts of an old PC PSU? Thanks

@arjunmaini28 6 лет назад

Sir please explain how this transformer works ...and what should be proper windings number for 5v..1 ampere transformer..smps

@radius.indrawan 6 лет назад

"the conclusion is.. it's rubbish." 😂😂😂

@dhiaa12 4 года назад

😂😂

@macoydiaz7747 3 года назад

I just wish my high school science prof was good at explaining as you

@conesillyvalley7182 6 лет назад

What's the purpose of 2.2nF, 1Kv capacitor? Seems like providing AC ground reference for output AC ripple.

@hanifpathan5466 4 года назад

please sir tell me how to connect yellow multimeter to get wattage

@chucky-ky5hk 3 года назад

hi i knew right away that you are a neighbor from cz, otherwise a good explanation :D

@rickysambora8321 2 года назад

Great video! Thanks. I almost but that thing. Do you have any recommendations where i can get a good DC adapter 12V 2Amps?

@douro20 6 лет назад

I've never seen that type of pipe clamp before; what is its manufacturer?

@user-dr4oh6zn4n 5 лет назад

How can I get the transformer which is used in the circuit??? Please help me if anyone can

@shahriarshakil9797 Год назад

Sir, today I have made this circuit by looking at this diagram, but no voltage is coming out at the output, please tell me what could be the reason.

@hassansaeed5894 6 лет назад

can u tell me what is the alternative of a 500uf 7.5v electrolytic capacitor. ? well i cant attached the image here to show u.

@____.__._.._ 4 года назад

What's the sense of placing optocoupler if 1kV capacitor connects mains side and output?

@GerYluKas4107 Год назад

Thank very much!

@tomkirkgaard247 6 лет назад

The diode in the secondary is only rated at 1 amp, that's a clue.

@DumahBrazorf 5 лет назад

Exactly. Because it only rectifies half of the wave the maximum continous output of the power supply is half of its rated amperage.

@Doggeslife 2 года назад

I was just looking at a large number of 6v 2A adapters on ebay, and they all looked like that one for the most part. Most curious, the photos of every one had the output specs printed on it blurred or blanked out. Thank you for the warning. That's why I came here.

@millamulisha 2 года назад

This is art. 🤗

@aaronn6725 3 года назад

What is a switching adapter? If I have a ac120v/dc12 and a ac120v/dc12v switching adapter, can they be interchangeable?

@deanslevin5511 4 года назад

The best RU-vidrs ever 👍👍👍

@ramakusrayoutube4436 4 года назад

How can i make this .5 amp to reach 2 amp any support to me will be well appreciated.

@Grace-py8bo 4 года назад

My adapter got blasted when I turned on wifi. Please tell me what to do..?. Will my wifi work.? Do I have to change my wifi

@superbaby3036 6 лет назад

Gracias Profesor 👏😃

@temporaryacc6063 Год назад

I have the same adapter for my mini tv, should I get rid of it?

@subhaskmandal4904 3 года назад

Very very good.

@kenarsuleyman 5 лет назад

"The construction looks very Chinese" -DGW 2017

@ix.cryo1 3 года назад

👁️💧👄💧👁️

@valshaev1145 6 лет назад

Why wouldn't show how to redo it to capability of real 2Amps?

@damny0utoobe 4 года назад

I gotta study these power supplies

@GerYluKas4107 Год назад

How about the complementary power amplifier? I want to learn it!

@fergiealex2613 5 лет назад

you have schemetic for adaptor epson L210 ?

@VicGreenBitcoin 4 года назад

Looks good! Where can I buy this adapter?

@technicalstatus241 6 лет назад

How does work axillary wending in smp tranformer

@KUBA64official 6 лет назад

Zajímalo by mě, jaké výstupní napětí zdroj skutečně dává při zatížení. Předpokládal bych, že takový pokles je do značné míry způsoben extrémně tenkými a dlouhými dráty od výstupu.

@nurmohammod1706 6 лет назад

KUBA64

@EJEuth Год назад

Have you seen such ‘Xing Ling’ SMPS modernized, using 1 MOSFET SSS2N60 + 2 auxiliary BJTs? In case you saw, or made a video, could you please share the link? Thank you And have a blessed Holiday season!

@africantwin173 5 лет назад

So which 2 Amp 12V on Aliexpress should i buy.

@German_byte Год назад

How does one measuring the quiescent power?

@SianaGearz 6 лет назад

There's this super popular power supply board in China, XK-2412DC. Would you like to get your hands on it perhaps?

@DiodeGoneWild 6 лет назад

Yes, I definitely would :).

@jangondrie4338 6 лет назад

Using this XK-2412DC supply: coudl I increase the voltage to 14,4 v???

@SianaGearz 6 лет назад

Yeah Diode, how do we arrange it? Do we sponsor you the purchase price, do we drop ship it to you, or do you just get one on your own?

@MoesKeckeEcke 6 лет назад

Siana Gearz ask him for his address with pm and drop ship as gif for him :-)

@DiodeGoneWild 6 лет назад

If you don't mind drop shipping it to me, I definitely won't refuse :). give me your email so I can send you my address.

@zikermu 4 года назад

you're great . Thanks .

@alibehrouz9833 6 лет назад

thanks man

@alexstone691 3 года назад

Im very intrigued a power supply could be made using no this simply, while this probably isnt that stable it still should be much more efficient than the old linear tech Im gonna attempt to build one of this myself, it may catch fire though :D