Bloody hell is all i can say about this one. Studiying EE for 4 years now, took a break to watch a new video from my favorite YT channel. This is some next level engineering space magic, gave me a headache halfway through. Can't even imagine the amount of work and effort you put into this video, and i'm actutally glad you decided it's not worth repairing/not repairing it just for the sake of the video. It's appreciated, no doubt about it. My mind is simply blown by how far you went in on this one, and the fact that you're sharing all this knowledge for free. But you still owe me a fire extingusher for the headache ;)

You can hear the excitement on his voice when the PSU starts to smell :D

PRE-LIKING cause a teardown of an 850W PSU from diodegonewild IS going to be WILD!!!!!!!!!

Watched and studied it all. Repairing a new never used new Apevia Signature ATX-SN1050W 1050W 80 PLUS Bronze Power Supply I bought for $10 on Ebay ...not working. I traced from 110VAC input to the outputs. Single cap for the +180vdc after the input bridge, unlike most with dual caps but that was the only power reading I was getting. Nothing was turning on. All the semicons tested good. So figured I need to find where the +5 vdc was being supplied from first ...the small transformer and associated ic next to 2 opto couplers. All looked and tested good and found the +5 vdc from that circuit. So i traced the +5 vdc from there and found a mini crack in the +5 vdc very thin 1mm trace on the edge of the circuit board at one of the 4 mounting corner posts. Apparently the box had been dropped with enough force to move the pcb enough to crack the trace. Solder bridged it ...success. Your info helped me track it down. Thanks

"This is dodgy, lets plug it in" This is why i love you . Stay safe though!

Even 3 yrs later, you still deserve credit for these schematic drawings. Must have taken a million years to prepare this video I guess. Always nice to see your cat help you

I really love the fact that he doesn't use ads in his videos or sponsors, greetings from Bulgaria :)

16:31 "So as you can see this power supply is properly exploded" I'm dead

I’m just halfway the video and amazed by the detailed explanation given. It’s a lot to chew on but very interesting! Your assumption that a screw might have caused a short circuit seems very plausible. Maybe something else broke down first and then after the first repair attempt the screw . . . ehm just screwed everything up.

I really would like to see one day a collab episode with DiodeGoneWild, Electroboom and Photonicinduction. It would be extremely awesome :D

Probably the most interesting voice and accent combo on KZfaq. Excellent video, thanks!

Wow so informative! I have learnt more from your 40min video than at school for a whole semester. You should get more attention because this is gold quality content!!! I like your work keep it up!

You are the king of the SMPS

althrough gruaduate of an EEE years before, still attening the PC power reverse Engineering course now, thank u,DiodeGoneWild, your are a good lecturer.

This person is just great. Being electronics hobbies I have an immeasurable amount of appreciation and for not only his knowledge but his generosity it making us so much amazing content. The bonus for me is no matter how shitty a day I have had, how stressed I am his accent makes it totally impossible to stay that way! So from me to DiodeGoneWild....thankyou brother!!

You are a genius... Can never imagine someone understand such a complex supply and explain it

the inverter was a lot more simple than i expected. makes perfect sense to me, just never learned how it was done before so thanks for the explanation.. awesome video as usual. best channel for tear downs on You-Tube!!!

Holy crap! That was super in-depth and understandable! Some of those circuit blocks are absolutely brilliant. Keep up the incredible work!

That was so funny...The cat....the primary paw, then the censored tail end....Very, very funny.

One of the best videos of this type I've ever seen. Packed with such a lot of useful information. Also looks like a good PSU for modding to run a remote solar powered computer set up, or just to use a PC on a vehicle, without having to resort to using an inverter. I'd guess many dead supplies like this have only the main switching section that has failed, so great for re-using and getting a second life as a battery powered computer PSU.

The reason i clicked was because of 80+ Gold PSU so I thought this might get complicated for him but i was wrong

Sir, you and your sense of humor make learning electronics a whole new adventure. I must donate !!!

What amazing insight and experience you bring to your videos. I'm studying EE and recently power supply design. I love what you are doing, your sense of humor (and your cat). Thank you.

"I can smell something beeehrning"

I've been looking fore something understandable about ATX power supplies since I'm into electronics. And finally after years I found it :D Huge thanks!

I have a similar 750W P/S needing repair so I was looking forward to a full repair of the one in the video, but I understand the reasons for not doing so. Sometimes the damage is so great as to render any repair effort too costly in time and materials, especially when inexpensive replacements are so readily available. However, I do appreciate the detailed walk-through, and the experiments with the working sub-sections were very enlightening as well. Love the accent, BTW, it forces me to listen more intently and I therefore learn more.

The amount of knowledge and detail of your explanations are simple incredible, keep such a great work!! Hope one day I become at least a 50% as good as you are with electronics!!

"Octa-coopler" lol. Awesome video, incredible detail and a thorough explanation! Thank you!

I work in a company where we design these power supplies with even higher power ratings. I am currently working on a 3kW AC-DC power supply. I really appreciate your knowledge and the ease with which you handle these things. I am new in this industry and I struggle to understand the supply if I don't have a schematic and PCB layout with me. So I am curious to know if you actually draw the schematics from your own analysis? If that's the case then you are a super hero :D Plus, your cat makes the videos even more enjoyable!

WOW! A very clear and concise explanation of a very complex switch mode power supply! Excellent job sir! You really know your stuff!

Duly posted on EEVblog under reference under Electronics primers, course material and books section.

Really great information about pfc atx-power supplies. Thanks it was nice to watch and learn something.

That oscilloscope is from the USSR. Man that thing is cool. I like Soviet era electronics and mechanicals.

Thanks, Dude. Excellent in every way. You're a natural teacher. Keep it up, please. Can't wait for future uploads. BTW, I have a Gigabyte badged power supply that I won in a computer magazine competion but blew up on first use. Haven't got the heart to throw it away, sentimental reasons, but happy to donate it to you.

Wow! Watched the whole thing. You've got it down my friend. Wish i had your EE skills. Super informative vid. Keep posting.

Talk about going beyond the call of duty. I learned so much from this one video it's amazing. Thanks so much. PS. I love your accent, it makes me smile.

He is doing it right when he said "Do not remove this cover I'm just joooking"

*FULL BRIDGE RECTIFIER IS NOT A PUNY SINGLE DIODE!*

My trusty Cougar CMX 800W went south recently, with a loud bang, during an attempt of powering up a PC after a couple of weeks of standby. I am watching this with a tear in my eye. But it has served me for some 6 years. I will attempt an investigation after setting up a bench.

DGW is so knowledgeable, he must have a doctorate in electrical engineering.

I don't understand most of the thing you say, but still enjoy it.

The best EE channel on youtube hands down!

I have the same Makita:-) one go the best small battery driller and very strong:-) working fine over 8 years, and I'm using it almost everyday! Grate video like always, thumbs up 👍

I've been watching these videos lately. I'm really amazed at the skill and work that you have been giving in reverse engineering these SMPS circuits. I've learned a lot on your videos specially on understanding the general design of these power supplies. I've really gained confidence in tinkering with these devices and understanding its complicated circuitry. With your video I have fixed several power supplies mostly ATX power supplies along with some exciting fireworks on the some. So with that I would like to say Thanks! P.S. Would it be possible to make a content on the common failures of these power supplies and what could possibly have caused it. Most of what I have fixed are failures on the capacitors at the output side. And those that made fireworks and big bangs are usually exploding NPN transistors at the primary side.

@DiodeGoneWild I'm glad you left your cat in the video. He or she looks so adorable.

Love that long troubleshooting & explenation Videos from you. Great Video, thank you!

Best commercial on why $200 is not too much money for a PSU

Thanks . It help me alot to knows the way of complexity powersupply how it work . This things take alot of time to know . Thanks

Another very entertaining and educational video...thank you.

My respect for you is directly proportional to my misunderstanding of power supplies. 100%! Thank you!!

Thanks for sharing with us! Very complicated circuit, and you probably took some time to investigate all these circuits. Very nice!

Man....that was like being a kid and finding out where milk came from....I just lost all the magic of the "80+" and gold certified and why they cost so much....other than using more reliable components Its really not a expensive item to manufacture.... great job....DGW

Power supply videos are the best ! great explanation

OUTSTANDING - Xtal clear explanation. THANK YOU

Best lecture ever about power supplies , your video was very informative to me , a tons of knowledge , I wish you a good luck & thanks a lot .

Awesome explanation my friend!! You sure know these confusing supplies very well. Love your humor on the subject as well. Thank you!!

thank you for such a detailed description and explanation of the working, I want to build a similar supply for solar power panel in series with the power correction for open cicurt voltage.

If you were my Physics teacher during Bachelors, wud have never got KT in the exam! Good going man!

I loooove your battery backup idea. I may expand on that and make a... safe... version

What I reckon is the feedback transformer is more or less a 1:1 turns ratio isolation transistor driver transformer. Where the fault occurred (a stray solder-ball, screw, wire, etc), the primary side transistors went into shoot-through and blew the driving components... don't be surprised if one or both of the main power-fets are short circuit (or at least degraded). A pulse of high current very likely got sent into the feedback transformer and induced a voltage on the secondary (Driving side) overcoming the breakdown voltage of the main driver IC+circuit. This allowed a large current to release magic smoke. An example from work, we were trying to figure this style of circuit out for an LED backlight system in an older Samsung screen. We landed up being trolled by a fried feedback transformer (could be a cause or result).

Best video so far, I really enjoyed this detailed deep dive into the function of power supply components.

Fantastic Video! Thanks for all your hard work. Extreme effort for sure. It is very much appreciated! I have a few repair videos and I try to explain what I can, but this is some next level digging in and understanding!

Fantastic explanation on the Active PFC. I always wondered how that worked. It's more complicated than I expected!

Just FYI, the resonant half-bridge is used to reduce (eliminate) the switching losses of the mosfets. Thanks for the amazing videos and keep safe. Seeing you test 360V dc so casually raised my heartbeat.

Do you need anymore power supply donations? I have a very high end pc power and cooling turbo cool 860 watt psu that stopped working.

Absolutely usefull to watch this video. There was a lot to learn about things totally new to me, especially in this detail. Exactly the usefull details, very clever and good to understand drawed and explained. Indeed, this was very worth watching with full concentration. Glad i did, and some of the most interesting bits i had to watch a second and sometimes a third time to get it really, to learn it usefull.. Oh I simply love this channel. His real usefull knowledge this clever diode teaches here, and even for free!?

Very interesting learning about how these things work! Also answered why some newer PSUs have significantly different sound characteristics at low loads.

It's so easy to fix broken power supplies when you have the help of a cat!

Thank you very much .you explain accurately and clearly . One of the best I have listened to here.

I like that Soviet made oscilloscope that you are using - Sdelano v SSSR. You are doing wonders here with electronics bro, keep up the good work !

Just exploded my PSupp fuse entirely - this vid is pure gold and the cat - that's a proper dude who makes space for his furball!

"I won't step on the primary side of it!" = AWESOME!!! Safety cat! :)

Thanks for being meticulous in your videos.

That flat PCB switch is nice

Awesome vid, very informative, teaches A LOT of stuff. Please keep up the good work!! Liked, loved, digged, everything. Primary advantage of old and cheap switching PC PSUs is (I think) that, being them relatively simple, they are quite easy to fix in comparison to newer and more complicated ones. This one is sort of an overkill on every aspect with many SMDs under the PCB and a lot of discrete controllers, not to mention the much more cramped space in which we would have to move. Enermax builds amazing PSUs which fail rarely, but they seem quite hard to fix if they fail.

It is quite likely that the 1N5406 diode in the aPFC circuit is not just used on the initial charge of the output caps, but also in standby mode. It's state of the art since years to bypass the active PFC in standby to reduce standby power. PFC is required in the European Union for loads of 75W or more, so there is no need for the "overcomplicated control circuit" (quoting DiodeGoneWild) to run in standby.

I appreciate your effort. You didn't repair the supply and IMO it wasn't worth repairing anyway. But you are a very good engineer. My salute to you!

you got a nice project box with a fan 👍 I love switching power supplies, there is a lot of useful components to reuse ( if not blown 😂😂) big blue thumb 👍👍

dude. you are very good at teaching. thank you.

Nice video, though you didn't repair that power supply but you explained how it supposed to function in detail, i really appreciate your effort, thanks.

You are becoming one of my favourite youtubers. Keep it up

You are very well trained in electronics.

The dc-dc converter is the LLC topology. It's a variable frequency fully resonant design operating above resonance. It has lossless switching on turn on and turn off edges so is quite efficient. Power output is controlled by increasing or decreasing the frequency. Power output increases as the frequency is lowered and approaches resonance, but must never reach resonance or lossless switching will be lost. The topology has pro's and con's but does result in quite a high power density supply. The dynamic range of the LLC topology has a limited dynamic range and is best run from a pre-regulated PFC stage. This topology is often used in 48v telecom PSU's for efficiency reasons. They are more complex to design than PWM converters and I always relied on computer modeling and simulation. Also, they are unbelievably quiet from an EMI perspective due to the soft switching.

Thank you so much man. You are the best electronic enginier that i know. I impatiently waiting for your next videos

suuuuch an amazing video. You are a genius! Some people dont understand those thing. Others do but have no clue explaining it, because everything is so easy to them. you on the other hand besides beeing fun to watch because of you accent.. no i mean because of the things you have and use and do, are explaining it just step by step

This is Dagne I injoy the explanation of Power circuit I enjoy your cat TOO

Very helpful video 👍

you r very good elecronic man..look at the scematic make me mind blowing..goodjob

its some university courses in action !!! EXCELLENT!!!!!

A great explanation of a complex circuit

Terrific video. I learned a mountain of information.

Best SMPS guide... bravo

Bravo! Absolutely fascinating, useful and thoroughly enjoyable. This 50 year old ET found it easy to follow and well worth watching but think any ITS, Raidioman, or RC Hobbist would really benefit from this High Power Switching ATX Power Supply works. Nice forensics too on how you identified the likely failed components and used clues to identify the source of the short. #electronics #maintenance #powersupply

That czech accent is hard to miss ;-)

Excellent, as always you are really good at explaining different SMPS topologies.

What an enormous video!!! You made my day. Thank you so much for your big lesson

Your awesome knowledge combined with your great videos steals many many hours of my free time. And it's worth every second! ☺ 👍Keep it up for a long time!

I had almost the same series power supply from Enermax (Revolution Xt 730 W) and it worked well for 4,5 year until I installed new GPU (VEGA 56). When PC was idling there were no issues, but under heavy load PC kept shutting down or motherboard triggered ASUS Anti surge protection even though my real consumption was 660 W (AC) or 600 W before losses (DC) and I heard also PSU relay click. I suspect capacitor degradation causing undervoltage triggering either inbuilt PSU protections or motherboard protections

Very interesting ! Thank you. I noticed the CCCP on your oscilloscope.

Regulation will be achieved using the PFC voltage, rather than some complicated frequency change altering tuning. The turns ratio of the main transformer and the input voltage are all that's required for regulation when the output has synchronous rectification (MOSFETs used in secondary instead of diodes). The two 100nF 800v caps are there to make sure that any DC imbalance in the drive doesn't end up prematurely saturating the transformer. (Imbalance being one drive MOSFET being on slightly longer than the other, which is almost impossible to prevent).