Tiny Li-Ion Charger with no Chip. Schematic & how does it work.
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- Опубликовано: 28 авг 2024
- I'm testing a tiny 18650 Li-Ion / Li-Pol cell charger and then taking it to bits, including an autopsy of the transformer. It contains a 2-transistor switching power supply with no optocoupler and a Li-Ion charging circuitry with no dedicated charging chip. There are just two transistors and a TL431 voltage reference. I reverse engineer the schematic and explain how does the switching power supply and the charging circuitry work.
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Even though I went to University, and we learned a lot about the math involved in the electronics, nothing is better than looking at a circuit and know how it works without even a single calculation!Thank you Mr DiodeGoneWild for the efforts you're making to make people understand electronics in a very intuitive manner!
you are the master of finding dodgy chargers and batteries.
The way you explained the circuit made it easy for me to understand
These vids are invaluable. Thank you for this knowledge.
indeed
Thank you very much for this schematic! I just built it. It works nicely!
You are VERY GOOD! And I like it very much that you give your viewers the SCHEMATICS of the unit you are evaluating and explain how the DIFFERENT PARTS WORK. You are SUPER! Pls don't change your presentation style - specially giving your viewers the SCHEMATICS and WALKING THEM TO HOW THE CIRCUIT WORKS. Thanks.
It seems ookkkkkk
Milliaaamps
Insiiide
Screwwws
In iiiit
I love this guy
*scryuuuuus
There are only two dodgy sticky tape layers in this tra'ansformer! Between you and mains! I heard that a lot!
dodgee English but we like it.😂
*Optacouuupler 😂😂
degurus, dogey, opto cuplar, r u kiddinggg mee guyss me to love this guy :)
That guy is awesome!
He's got a super cool accent.
But he is cool.
'But' is used to separate contradictory points, 'and' is used to separate complimentary points.
I'm almost less concerned about how good or how much tape there is, but whether the wire that comes up to the wires could come close to each other. Sometimes they end up wound such, that the primary and secondary cross right over not far from the terminals.
You're right, the primary and secondary may sometimes meet each other near the terminals.
Fascinating how every company have their own low price cheap circuits which makes our life better or sometime worse 😊
Really, your classes are great, please activate the subtitles, because I get lost in some parts.
The transformer was definitely not as bad as i expected, and from the outside it didn't look as dodgy as usually with those chinese cheap devices! The isolation distance on the board is also not that bad, even thought of course it is still not as big as i would expect from a good power supply! I am also surprised in that they used a TL431, but they didn't even bother put a bridge rectifier in it, and a bigger primary smoothing capacitor!
And of course... after reading this you might think it's not too dodgy but... THERE IS NO FUSE!
Im impressed. Very clever design. Thank you for presenting it.
Amazing as usual. But, given the tolerance of the components (20% on caps), how can this be safely used? You could do a video on tolerances and actual circuit performance.
No, not safe, that does not compensate for a lot of variables especially temperature. It's wildly complex and even the most fabulous illustrious and illuminated enginleers can fall from grace in their righteous crusade to empower us all!
Our wizard enginleers decided to use a single bare AA lion for nvram backup on an embedded controller. They serially screwed up a charging circuit based on the ever so cute ST microprocessor that 'did it all for us' YAY one world lion revolutions! It took 4 years after product release to get it to not destroy batteries.
First bug ST helpfully would randomly switch to battery backup, not programmed, no warning, no way for a humble mendicant to disable it. We had to go to a turd party bios to fix that one, not sure if there's tertiary uber secret Grout Society 99th degree masonry NDAs or what but nothing worked.
2nd bug, temperature. Our illustrious and illuminated engineers depended on the temp sensor in the STM processor. Yep.
3rd bug the colorful balloon animal chart provided by ST for this processor is incomprehensible. It's not a flow chart unless you consider balloons have air that flows out when you pop them and there is no reference charging code. So when you charge at 100ma the processor says it's a balmy 30C and the -40 lion dies.
There are other hilarious disasters.
Such as our miraculous and sanctified enginleers deciding to compensate for the nvram failure they in collusion with ST cause by flushing nvram to flash on power down by...yes you guessed it draining the lion to power it briefly then they find after releasing the firmware that the dependable and miraculous ST processor forgets to turn that off, yes it was programmed to go off. So they had to do some FPGA hack they won't admit they contracted out to get done to sledgehammer the ST processor OFF as no hardware design budget left.
Now that it's perfected (see infinite hairy belly lauff track on utube) we've lost several accounts and no one wants that product line. They're *squee* redesigning it like a bunch of unsnipped catgirls at a Cthulhu convention. Yes TPTP are still letting the children use the most wickedest of "state of the fart" with no adults in charge. They chose to replace nvram/flash with I think nonvolatile FAPRAM....which no longer exists as it went obsolete in 2 years and are glaring at a replacement offering of a subtly different tech are $40 each chip and hardware and code changes are needed. Sweet. But they did go back to a primary lithium battery which works after they fixed reversing the + - pins.
Nice video. Thanks.
For comparison would you try to tear down a good quality transformer for comparison ?
The tape is no ordinary tape but high isolation tape and the wire is enamelled so how does it all compare to a good one ?
such a great explanation.
"There are tree scrius" I love this channel!
They put some work into that one, even a slot to help isolate the transformer.
I would not of worried about the transformer, that wire looked fully coated, and neatly wound.
Laquered wire + tape + laquered wire.
The circuit was quite clever, simple but clever :-D
The worst thing about those transformers is that the primary and the secondary can meet near the terminals if the transformer is wound lazily.
Thanks, it’s a strange configuration with the input of the NPN being the base of the PNP. Indeed as you say tricky because the NPN flow through must bias the polarity potential of the PNP base in reference to its input for it to function in an ‘on’ state, I don’t think I’ve seen that before.
stfu wannabe smartass
The transformer windings are made with enamel insulated wire. It looks like bare wire, but its not. As long as the enamel is not scratched or burned off, the tape separator is fine.
I'm tempted to try this charging circut myself with junk bin parts. Thanks ;)
Put an RCD clamp across the primary and at least a fusible inrush limiting resistor and it should be not as crikey as it is now. :)
He probably ment to build just the charging circutry without the power supply, running it using another low voltage supply.
Yeah, I'm mostly interested in what I can build for free to try to make (dangerous) use of some old unprotected 18650's from old laptop battery packs. I'm only interested in the charging topology. I haven't seen any info or circuits that do this with just passive components and just a Vref IC. The circuit appears to lack the CC/CV control needed for proper lithium battery charging, but it's simplicity is still interesting. Anyone can build this charging circuit with upcycled junk. It's a rather useful circuit that doesn't require ordering parts and waiting on shipping. You can build it on a whim, on a Sunday afternoon when you just want to finish a project on the bench ;)
I was tested and IT works.
Nice video ! Best part of the video : 3:06
As a roule of thumb, I worked with a difference of 1000V could create a 1mm ark in normal air. So i guess the tape is okay under good conditions, but eventually it would break down from heat/cold and oxygen.
Thanks for the content. Very ell explained, easy to follow.
By seeing the secondary lithium charge control i believe that the circuit must oscillate on off badly when cell reaches the termination voltage. These circuits need an precise charge termination topology like a comparator with hysterysis would offer.
I don't think it oscillates. The capacitor near the TL431 (100nF) prevents oscillations. The 1ohm resistor brings some hysteresis, so it turns off decisively when fully charged.
download LTSpice from analog.com for free, capture the circuit and see if it oscillates. It does not. It is true the 1 Ohm resistor makes positive current feedback, resulting in negative output resistance (output voltage rising with current), but it is stable.
sir
what is the role of auxiliary transistor !?
someone please explain.
The auxiliary transistor closes a power transistors gate/base to ground. In this charger it closes, if overcurrent was detected.
good explain sir
Could you tell me what the value of the Zener Diode is on the primary side.
I love all your videos.
I would love to see you do a teardown on a inverter.
Excellent!
Great stuff. Would be nice to have the specs for 3 Gauge wires. Thanks.
Great job man.thanks a lot
Verry intrasting nice
if you would just loose the wierd "dialect" otherwise...you are obviously a genius at deciphering designs....so thankyou
great explanations👨🔧👨🔧👨🔧🕺🕺🕺im learning!🙆♂️🙆♂️🙆♂️
good job
Single diode rectifier at input helps blocks reverse input voltage
tell to the namak chhap to measure the thickness of enamelled winding wire by SWG gauge .
If they used proper insulation tape in addition to triple insulation. wire the setup of the transformer should be sufficient
That 18650 battery 9900mah. Why did you even buy it? Lol
For testing, for fun and as a guinea pig :). Actually it is about 500mAh.
DiodeGoneWild. 500mah thats crazy. What did you pay for it?
you can get 4 of them in a pack for like 5 to 10 euros on ebay(dollar prices are simmilar)
Против Глобал . I take them from laptop batteries. Some companies have a small container where they put them in for recycling. I have about 10 batteries and each containing 6x 18650. The portable drill batteries are the strongest ampere ones. I stopped getting them for my projects because i have enough of them now.
Grazie fai video molto interessanti. Grazie grazie grazie
Good job
I like if i can make it at8.4 volt and the circuit thanx
What is type of auxilary transistor?
What type pnp transistor
becus I charger stop on it
IT'S OVER 9000 !!!!!!!! lmao !!!!! im done, lmao !!
looks like it newer fully stop charging the battery, resistor bypass transistor
Hopefully, the TL431 can somewhat sink the current of the bypass resistor...
Nice
3:07 audio and video are not in sync.
Output Voltage 4.2Volt Plus Minus 1 % 😆
I cannot understand: how can it be economical to produce boards with lots and lots of through hole components, or in particular, why would that be something they would do in low-end devices? I mean, SMD, you get your pick and place robot, you bake the board, it's automatable, plus components are often times cheaper. With through hole components, to the increased cost of components, you add a cost of installing those components per hand, of about... well it's not TOO bad, maybe 0.3ct per component, but it adds up!
Siana Gearz it's made in China, that's why.
Sooo? The hand placement i estimated is based on Shenzhen costs - the pick and place machine for SMD components essentially runs for free. A quip "because it's China" is not good enough, i need a specific piece of engineering/cost analysis or situational information that explains why a through hole assembled device turned out to be cheaper to make than a machine assembled one.
Because in China, human work is cheaper than a machine. There's also a momentum of through hole technology. And finally, some of the components may be reused from e-waste.
Siana Gearz Also there exist some semi-automated through-hole assembly systems.
Surplus non SMD parts are almost free. Labour in China is cheap. No hi tech equipment required. Anybody can put them together with one day training.
Can you do a fake nitecore d4? Mine works great and i got it free with a dispute.
HEYYY.Are you from czech republic ?
Yes, he is.
Áno je
No, he is Hungarian
Yep
Ta výslovnost je otřesná.
Where is my cat
What's your name and where you from please?
He's from Czech Republic ruclips.net/video/9AH-VIyzS5A/видео.html
en.wikipedia.org/wiki/Czech_Republic
Who ll give information about the thickness of those winding wires. Probably Namak Chhap
9724099300 for Drugs n koken plzz contact ..namak chhap
9900mAh? Were tf did you get this fake 18650 Cell 😂
Ultrafire 18650 cell on amazon for 1$
And yep those are fake real capisity is around 500 700 mha
Great work man, keep it up.
But that Li-Ion battery seems fake with a rating of 9900 mAh! 0:15
People be aware of these Chinese batteries with crazy #s
Original ones(Samsung...etc.) are rated in the 1X00, 2X00, and 3X00 ranges. (X=0~9)
the 9900 mAh is definitely fake. Actually it is 500 mAh. It is just my guinea pig.
Ok, also I think the life-cycle (how many times it could be recharged) is kinda low on Chinese batteries.
I tried the LiPo that came with fake eGo e-cigs
duckduckgo.com/?q=eGo+e-cigs+battery&iar=images&iax=images&ia=images
Keep up your good work man, and never mind those who talk about your accent, you are providing people with good information. Good luck
I guess the transformer manufacturers are getting away with this type of design as it doesn't appear to have changed over the years and not many people dying. One or two, well that'll happen even with the best built product.
9900mAh 🤣
That battery is a fake... There is no 18650 9900mAh
Of course it's fake :) its just my guineapig.
win SUB
Why are you singing while you speak ???????????????
lasersbee Everyone sings while they speak. Have you ever listened to someone speaking in a language that you don't understand? The illusion of pauses between words is caused by your own brain...
Laserbee
Why aren't you thinking while you speak?
What does your great collection of question marks me signify? Bit silly really!
You have clearly never enhanced your education (education eh?) with a learned foreign language otherwise you would be aware that a learned language is heavily influenced by some characteristics of the native language which I suspect it to be Czech.
An' you jess gotta be American.
MauriatOttolink.. You have clearly never enhanced your education with that non-educated nor fact based comment. FYI I speak 3 languages and am not American... But thanks for your uneducated nonsense response.
i love his style, it is funny
Hello et alors cela me fait une belle jamble hi
İ was thinking you are indian beacause your accent is similar.