Questionable 2-in-1 USB charger - test, schematic & modifications
ฝัง
- เผยแพร่เมื่อ 12 พ.ค. 2019
- I thoroughly test and examine a cheap two in one 5V USB charger with a 100-240Vac mains input and a 12-24Vdc car input. I take a look inside, reverse engineer its schematic and explain how does it work. Then I try to do a lot of modifications to the circuit. Surprisingly, this doesn't go horribly wrong, just horribly long :).
Even more improvements of the buck regulator:
• Building a better buck...
You can support me on Patreon:
/ diodegonewild - วิทยาศาสตร์และเทคโนโลยี
No one on the youtube describes the schematics with such beautiful details. Good.
I give it "Tjuu..."
his videos is a CATantastic😼
12:47 so the mains comes in... and goes straight into the cat!
i love the cat, that's the best part of videos
I hope someday I’ll have the same level of understanding of electronics as your cat 🐱 has.
And oh yeah, to reassure your cat: I survived watching the video right to the end.
The most questionable thing about this charger is the shape. If it wasn't because of the title, I would've thought this is some kind of mains powered vibrator thingy.
Mains powered vibrator from China sounds like a disaster, sure would add a bit more tingle due to poor isolation LMAO
It's a portable rechargeable mini dildo
What fills the heart, will flow over from the mouth (or keyboard).
It should be used on the designer of this product.
everything is fusable if you pass enough current trough it.
Good informative knowledge shearing Thanks
Everything may also sustain an arc if you pass enough current trough it.
Talonfluff - unless it goes short circuit!🤣
DiodeGoneWild hiiiiiiiiii I like u
@@Mark1024MAK there is no short-circuit with absolute 0ohm resistance .. with enough current any short-circuit can be made open circuit 🙌
Try to power that charger with 240v and 12v at the same time in order to get 1Amp :-)
The cat is like, "why is he yelling at this piece of paper with weird symbols on it instead of feeding me?"
Thanks for all those experiments and modifications to let us understand the effects of the components can improve the overall performance!! Still waiting for the big ATX power supply test, schematic and also the 24v power supply modify into a bench power supply. Thanks alot @DiodeGoneWild!!!
To cat: Never sleep a second!!
"Where's the EMI filter?" dying xDDDDDDD
DDDDDDDDDDDD.
Good video. Very cool oscilloscope. Сделано в СССР
strong soviet technology xD
"The LED comes on with no explosion" I love it how casually he is saying that haha!
I love the different experiments you did on the component values. It's hard to beat the instructiveness of just showing what different parts do.
Your channel had quality content about power supply
You can even make your own design and repairing, we want more Repairing and diy power supply
We appreciate your hard work
Thank a lot 👍👍👍👍👍👍👍👍
He already has many very interesting DIY staff on his page danyk.cz/index_en.html
I personally like the non-diy-content a lot, like this video. It's always interesting to geht those devices explained so detailed.
@@DrHouse-zs9eb just diy power supply because he had a lot of knowledge and can easily design a much powerful and simple design compare to Chinese one.
Please tell me what group you are speaking for, you twice used "we", does that include me?
I can't recall to have been contacted by you to ask for my opinion.
Next time please leave me out of this, I can speak for myself and so should you.
@@ZZtop-gg3lu - itno akharo
I'm so happy you do all these tests with these weird products !
We get a lot of useful info !
And you're very funny :)
Charrrgerrrr!!!
DiodeGoneWild Hi
I just rewatched this video. I think it’s one of your best about smps. This is because you show the effect of the different components by changing their values. And showing the pwm signals was also quite informative.
Thanks 🙏 (to you and your cat of course).
You are the role model for all the technical video.
You ate very specific in providing data.. voltage current. Circuit diagram. In 5v 2a mobile charger you could not find part no. of smps ic. Left it with question mark. After some time updated circuit with correct information.
Thanks for your interest and initiative. I have gone through most of your videos. You provide cost and source.
Thanks
Ashok
Banalore
Appreciate you showing us the scope, a lot of YT channels can't be bothered with the second camera setup to show the scope... but it makes it loads clearer what the circuit is doing.
Cat probably hears you talking when there's no one else there and decides that you must be talking to her - I've got gamer friends and their cats all want to walk all over the keyboard when they're talking on the headset.
The cat usualy lays on the bench before I start talking. It seems that the cat's are attracted by something else. Maybe they recongnize when you are just about to start doing some hard work and they want to be helpful or learn something new or have some fun.
Epic video. I enjoyed the cat & thinking about what parts changes might do both in theory and in practice. Need to watch this a few times!
Great video. Unbelievable how dogie this and many other products are. I test all my switching power supply wall warts now from mains isolation after seeing yours and Bigclive's videos.
I guess I have been lucky. So far most of the units I have tested do put out rated currents. THANX.
Tx again for a nice video. I appreciate all the effort you take to reverse engineer this charger, draw a complete schematic for us and explain how it works!
Strange device. Why would you want to combine a car and a mains charger anyway?
Surely you can work out why a dual-powered charger would be handy?
For example, when travelling.
John Coops
When traveling I’d take a small mains charger and use a small 12V charger. This thing is larger than the 2 combined. I don’t see an advantage in combining the 2 functions.
@@Conservator. - I take a 4 port Orico charger that runs off 12V as well as mains. Much easier!
Please do more of these long videos, you're the best teacher of this subject on TH-cam!
nice explanation! I hope get more of this type of stuff. You explain the schematic, how it works, and try to fix it very well.
13:40 , the cat was trying to explain the secondary circuit😂😂
If it's a fusable resistor which also works as a fuse it's GOOOOD but if it's a normal resistor it's not so GOOOOD
I love your voice dude
LOL DGW. Your cat wants your attention. I love watching your videos - I’ve seen almost every one. I can’t get enough of your interesting English accent and well-explained and entertaining videos. Please make more at higher frequency :).
Awesome Video! You had me glued to the Monitor until the end. :-)
i like the different format, modifying something till it reaches the expectations and exactly how and why you change components.
i would like to see more, thanks
I Agree! It is even more instructive than stopping the video at the fail-point of the device.
The input has (primitive), interference suppression - the combination of the questionable 2.2uF, the dodgy 1 Ohm resistor and the forward resistance of the single input diode. These will probably start to roll at about 200KHz! Could be tested? Yet another great video, many thanks.
Excellent video. Learnt a lot from your efforts to improve the output. Great fun also.
One of best videos yet! Love it.
Always wait for amazing explanation , bcz you try best to express
You went really WILD! Nice video!
Yes kitty, I’m still alive and entertained and educated!!!! Love your channel and the details you dive into!!!!
Love the cat making the schematic a secret.
Yeah still alive till the end. I like when you play around with the components and then we can see what the differences are in the output. I was expecting you to put a full bridge rectifier on it.
After increasing the smoothing capacitor capacity tenfold, the bridge rectifier wouldn't have any significant effect.
@@DiodeGoneWild Right. Thanks!
Very good video!. I love watching this while im having tea.
POLSKA TO OGLĄDA :) Hi i'm from Poland and love Czech
I'm from Poland too! Great videos! Keep 'em coming!
Watched right to the end :) Your vids are the best.. Thank you!
Man I love your videos keep up the great work
Probably your best video yet. Many thanks. The experiments are very helpful.
Thanks for your holy wealth of information, trully valuable and something I wished I had when younger
dang you cat is smarter then mine... mine just ignores me and only enters my present when it wants something other wise it just ignores me.. I enjoy the heck out of your breakdowns of these products and there electronic boards.. I am 67 and am trying to teach myself a new trick.. Your breakdowns are helping my understand how it all works.. thanks my friend I enjoy your shares... carry on!
That was a good song! You are a great singer!
SAVAGE modifications - hacker APPROVED!
Your cat wants to replace the fuse. Great review.
Super lesson. Please make it more. Bay.
Hey man really love your channel! there are very little channels on this level
Just as an idea - can you make some videos on motor drivers VFDs servo etc?
This topic also relevant to high power and introduce some complex issues like back EMF handling and control loops over fast switching
The trace measured against the current sensing resistor doesnt look straight so the inductor on that buck converter was getting saturated. A bigger inductor will enhance the efficiency and just a bit more current at the output. Undoubtedly the 34063 was getting very hot at the higher load current. I have used this buck converter many times before but nowadays MOSFET based chips with synchronised architecture produce very high efficiency. The video you made today was very detailed.
Really nice and informative video. What will happen if you change the secondary winding with bigger core size. Will that improve the current capability? or will switching transfer just explode?
Amazing videos, very helpful and entertaining
your cat always cracks me up mate
great video as usual. the buck converter seemed to change its switching timeperiod between 10uS and 15uS with a change in input voltage. any idea why?
I love your videos. Hope to have some beers with you!
Excellent video
Its good lesson of smps
I looking for this video long time
I question core saturation of the output inductor of the chip. That steep rise in current suggests to me, that the current limit is tripping at that point. A larger value of inductor, with enough ferrite to handle the magnetic field would probably help with the output current. Also, it could have enough DC resistance, that the pwm is saturating, but that would be overcome if 24 volts is applied. It's most likely core saturation. The sudden spike in current is what trips the current limit, which is why there was not much change, when a lower value current limit resistor was installed. The spike caused by saturation occurs so quickly, that it's hard to see on the oscilloscope.
Strange looking charger! almost a 3-in-1 device!
Charge your phone with it for a while to preheat it for more plesure.
So the third one is for girls only
@@ex-soldier4341 lets not jump to conclusions now
@@lakiza55 that's what came to my mind a toy that rumbles😄
I've learned to never insert something into my ass if it can detach, that's how I got the nickname "the slot machine".
The teacher is back. Nice
I love your cat !
I see that the flammability rating of the PCB is only UL 94 HB (horizontal burn; limited rate of flame spread, but not required to self-extinguish), to add insult to injury. (From what I've seen, reputable manufacturers mostly use UL 94 V-0 rated boards. The next rating down is V-1 which takes a bit longer to extinguish, then V-2 which still self-extinguishes but can produce flaming drips.)
I have the same chip in my car charger and it gives me 1A at 5.15v so it's possible to improve the circuit to make it quite useful.
And it also would be cool if you added some optocupler feedback to the mains circuit.
Anyways this kind of video where you're improving shitty circuits to make them something useful is way better than just a circuit overview videos, thank you.
I want you to reveal your face. ALSO YOUR ACCENT KILLED ME LOLOLOL
He has done a face reveal already
Can you show us the step by step process of how you draw out your schematics?
Thank you for all the great episodes aslo.
I think it takes about half our of job
What about to replace zenner diode to standard cirquit with optocoupler and TL431 reference regulator chip?
You are a very good 'Teacher'. Will apriciate if you can make some DIY useful home gadgets.
Very good work! Why don't you put a full Bridget rectifier to test?
As always a good video!
Ahoj, dobrá práce. Pokud by autor příspěvku něco takového vyráběl, koupil bych od něj. Na druhou stranu bych měl obavy z recenze mých výrobků .. :-)). Jinak ta nádherná Britka nemá chybu !!
The transformer seems ok, it should be capable of delivering 5W, with proper input filtering and regulation. But they really did some serious cost cutting on this one. Maybe there's one that does implement better regulation and a bridge rectifier, since it's marked on the pcb. As for the dc-dc part, i'd just go with an lm2596s board set to 5.75V(because of the diode) and dich everything above the diode going to the output and below the fuse, i used it for my tp4056 18650 chargers to drop 12v to 5v at 1A all day long.
Funny to see your cat playing with a fuse at the end of the video
thank you for make this video & good luck 💐
Fusible resistors are really just metal film resistors, but they are painted with special expensive fireproof paint. You can actually use a normal metal film resistor -- as long as there is nothing too inflammable nearby.
I love your oscilloskop.
That buck i.c is a bit limited so i'm not supprised that the output is weak, i've never seen any car adaptor that works well with that chip alone.
That flyback reminds me of those cheap 12V,5V supplys for hard drive caddys, very cheap and minimal parts, but they do have a mosfet to drive the primary.
The "Ring" power adaptor uses a fet on the output, thats much better :-).
Your cat is loverly, it wants to be near you even if it is being a pest :-D
I wish i had seen this video before my exam (it was on the 14th). It would've been a straight A (6). :D
Cat likes fuses :P good chalenge on improving the power supply as it goes.
Diode gooon waaaaild...i love u r talking...
I don't understand, why 2nF capacitor is not charged from start up resistor? Please explain it. Thanks.
Why not to try installing a bridge rectifier and an optocoupler?
U are simply great. I love your all vidios. U explain the function in detail. But I couldn't understand the purpose of 1k resistor and 10nf cap. Kindly explain.
Ave will finally have his rectumfryer.
Useful video 👍 very good
the ultimate cost cutting version will have the mains directly connected to the USB +5V and GND. no other components.
Salam kenal subscriber dari Indonesia. Cara anda menjelaskan sangat saya suka walaupun bahasa inggris agak kurang jelas...tetap semangat ya...👍😁😁
Very nice, it is the fist time i see a man trying to "upgrade" the amp and voltage chinese. :)
very good video, but if u can plc show us the wave form on the base terminal of the poewr transistor of such SMPS charger.
hello. what is the rating of your solid state tesla coil's (first one) ratings? i built it and it burnt the fuse and tripped the circuit breaker.
although it may be my soldering job too, but no arcs so far
Hi, great explanation as you usually do. pity that the cat is bored a little but after all your video certain things he knows all too well :-) a proof that you did not do was to add the photocoupler that was missing, maybe something improved in the stability of the output voltage ?
If I put an optocoupler in it, the stability would be way better. I could have tried to modify it to the condition before the cost-cutting. An optocoupler and its LED in series with a zener, connected to the output. The voltage would definitely be stable at least up to 0.5A, maybe 0.7A. But the video was already a bit too long :).
A proč jsi tam nezkusil dát ten graetz na vstup ? místo toho jednocestnýho usměrňovače ?
And why don't you try to put there an full bridge rectifier at the input ? Instead of half wave rectifier ? That could help in improving an current output.
Když už sem tam dal 10x větší kapacitu, tak by to nic nezměnilo.
Id like to see you put a full wave bridge rectifier in the circuit and make some other improvements
k
I figured only 1 12-24V spring contact was used, so when you made your leakage test you used both, one of which was not hooked to anything.
Is the connected one that is tested
Ahoj já vým že jsi z Česka.
Máš dobrá videa a dobrou kameru.
Fortunately well insulated.
The cat does have a look at the case.
I hope someone can help me out here. I’ll appreciate any hint;)
I don’t quite get the mains voltage part. The transformer would operate better at higher frequencies right? Was the frequency increased at some point or was every modification just about increasing the current on the primary side?
Secondly wouldn’t it have been an easy gain to replace the diode (1N5819 )on the secondary winding with a full bridge and therefore effectively doubling the current?
Thirdly: 13:47 “the feedback loop induces more current into the transistor” through the resistor and the capacitor. But a capacitor blocks any (DC) current. Is that why changing the resistor and capacitor values have hardly any effect? Should perhaps a FET have been installed in stead of a transistor?
Those are some good questions.
1. The modifications were to try to increase the duty cycle when the load is high. I´m not quite sure what changing the frequency would do in this case. But it won´t make it perform better necessarily. It could make it worse.
2. If you replaced the single diode on the secondary with a bridge rectifier, it would no longer be a flyback converter circuit: It would radically change how the device works, and it would no longer be possible to get feedback the way you can in a flyback circuit, among other things. Most likely it would just stop oscillating if you left the rest as it is and blow up.
3. Keep in mind that all voltages coming from the transformer are changing quickly, and are AC. So to charge it current has to flow through the main BJT´s Base, making it more conductive.
If you wanted to use mosfets instead, you would have to change a lot about the circuit. But in general you would be better off using a proper control IC, or at least an optocoupler as the feedback anyway since that is way more accurate.
Hope this helps.
You can also watch his video on the power supply of a DVD player he did a while back. He went more into the detail on how a flyback converter works in general there and explained it very well.
Basement ScienceE
Tx! I’ll go and have a look at the DVD video and then report back ;)
This is the video: th-cam.com/video/cX4q0e124C4/w-d-xo.html
Edit: watched 25minutes now and it starts to become clearer now.
Edit2: watched all 3 video’s. Re: 2. Bridge rectifier would prevent energy buildup in the transformer and therefor indeed change the fundamental principle of this circuit.
Re: 3 As I understand it, it’s not the transformer that is running on AC but it’s the transistor that steers the transformer by switching on and off. Isn’t it the transistor switched off by running enough current through the 10k resistor and thereby closing the other transistor? How is it turned on again?
The USB connector. Which is a little bit rusted. That's nice!
The connector may be reused from scrapped electronics, just like many other components in those cheap Chinese devices...
@@DiodeGoneWild I watched a video on TH-cam of salvagers in Shenzhen. They were pulling parts off mountains of boards. Then they'd bale them all up and ride them on the backs of bicycles. You're probably better off with pulled parts than the counterfeit ones anyways.
Is it not possible to have one input. Like 12v dc to 220vac?
have you tried powering your grid from a powerbank . or maybe charge your car battery from a powerbank .. who knows what ir is capable off ?
Waiting for Transformer autopsy, 30:22 minutes later.
.
@talonfluff No, everything is not fusable, the electronic components marked as fusable often fuses for a certain max current meaning it become open circuit when it fuses for an absolute max rated current. But the components not marked as fusable often become short circuit, remember this difference!!
I always hear "snapper" from you, instead of snubber XD
Why didn't you replace the zener with a proper opto-coupler and replace the single input diode+1ohm resistor with a proper bridge rectifier *_as well_* as the 22uF 400V cap and 5ohm (10ohm*2 in parellel) resistor mod you already did. I think it would work much better then. Thats what i would do.