Your channel has the potential to teach people more than the university.

This scematic-drawing is quite genius! How the hell you know so much about power supplys?

You explain everything very easy, so it's very easy to learn from you!👍😀

This is the best in-depth explanation of a switching power supply that I've seen. Thanks for sharing your knowledge.

im 5 mins in and never have a learned so much off one video and hes only just warming up

Very good explanation! Especially about the feedback circuitry. It´s by far the most complex part of these power supplies. When I started learning about switching converters, I originally wanted to build one with all _discrete_ circuitry. Then I learned about the insanity called feedback circuits.

Just came across your videos recently and I think they are very informative and well produced. This was probably the most complete description of a fairly complex SMPS that I have seen and I have never seen anyone describe the feedback mechanisms in such detail. Really appreciate that.

Wow, looking forward to the upgrades... One of the best videos on this topic which I have ever seen...

Mega video. So much information. Obsolete scheme or not, it provides so much insight. Thanks a bunch! I will rewatch it several times in coming weeks.

Fantastic review of the circuit. Best in-depth explanation I have ever heard. I can't believe you remember all the information without reference material. I guess that is why you have so many subscribers.

I arrived to your channel by accident and I'm enjoying it a lot. Your videos are the best!

Calling it excellent is an understatement. Amazing explaination.

This is one of your best videos man, if not the best

Thank you so much for this explanation! It's help me to understand how it's work, especially the PID of the feedback system

This is one of the best explenation on the HB converter that i saw, congratulation

These are my favorite youtube video's. The schematics with an explanation. They really help to understand the way the circuits work. THANKYOU!

Super video, perfect explanation of the controll loop stability.

This was very interesting. I hadn't seen this topology before, was impressed with the start up arrangement. Your cat is very cool!

Very good video and explaining. The idea to convert it to a bench power supply is very good too !

Výborný kanál o "component level" elektronice, díky za tu práci a gratuluju k úspěchu videí.

Excellent video! Extremely informative and educational. Thank you and keep making more videos like this!

I just found your channel. This is very very informative. I have not as I remember seen any such detailed walk tru a complex diagram. Lucky me I found your channel. Thaks for your effort. Wish I knew just a fraction of what you know of engineering electronics.

I could understand every bit of information effortlessly. You are the ideal teacher Sir. Please convey my regards to the cat too...

Well explained. At the first moment, I thought I'll never understand that. But now it's better. I'm an educated electonics specialist, but it was 30 years ago, so my knowledge is a bit rusty now. Thanks for brushing it up!

Your explanation is superior... I can not get out of admiration.

The startup circuit is especially clever. And they save an optocoupler and still have isolation between primary and secondary. It also makes troubleshooting easier because you connect the oscilloscope to the isolated part.

Thanks for this great review and in detail explanation of switching power supplies in half-bridge configuration! This is probably one of the most in-depth explanations i have come across yet! Looking really forward to your modification to a lab bench power supply! There are so many powerfull server PSUs out there very well worth beeing converted to bench PSUs :-) Some of them reach several kW of power and can deliver well over 100 Amps at 50 V e.g. But they are even much more complicated than this example ;-)

It's the best explanation of an SMPS that I ever heard, Congratulations 👏👏👏👏👏. No matter the language I understood everything. Very good 💯💯💯

I am new to Circuits but your explanation though complex is very captivating. I will watch again and again it awesome how you put it all together. Thank YOU Thank YOU so much

Fantastic video. Please keep making videos about SMPSs. Thank you very much!

Please do a QNA on 100k subscribers.

Oh your english is such a great inspiration to others learning it!

amazing keep going we need the push pull topology too

Another brilliant walkthrough, thanks!

I'm currently learning on how to use the TL494 and I want to try to build my own power supply with it. This is very useful, thank you.

exceptional intellectual or creative power or other natural ability- genius, now its 100k subs,good job bro

Thanks to a great explanation I understand more than I thought I would, certainly more than basic operation but goodness no's how you guys design these from scratch !

very good explanation! i love the black magic that power supply is made of..

This video and explanations is very professional. Top ranked.

Great Scott and you both e plain everything perfectly.

Superior explanation... that is really how it is... It’s worth to mention that half-bridge and full-bridge SMPS are more efficient, more powerful derivatives from push-pull conception - 2 alternately switching transistors, divided windings, 2 diodes which means double the power charging the coil which is collecting energy. Best wishes from Poland.

a phenomenal job by you and your cat! you guys never disappoint!

Your videos are very informative, thanxforyourteaching

Anything is possible when you understand the operation of something and what all the components do in the circuit. I would definitely love to see you convert a SMPS into a bench top power supply! Especially if there's two of them to get both positive and negative rails. A retail dual rail power supply is way to expensive but it's a necessary tool for electronic work...

Very keen to see your conversion into a power supply 😁

And that is pure knowledge with very much experience in background. I am really suprised with this wonderful and educational video. Great job and thank you !!!! Cheers

Your videos are extremely Knowledgeable and informative thanks :)

Fantastic. I fixed one of these yesterday. I thought it was complicated but not this complicated!

As an engineer, i learned a lot from you. Thanks a lot.

Congratulations. Good job.

I like seeing your pets in your videos. They are a good addition :)

Fantastic explanation.

Fantadtic video. Great job at explaining. Only thing i would like is to have pictures of the components on screen as you talk about them in the diagram. Thank you again.

Top notch video. Examples are crucual for effective and complete learning. I think.

I want that schematic Great explanation

You do great videos, you sound like you design switching power supplies for a living. Of course I noticed that all your videos receive a cat scan before they are released. That must be a great help!

I love this videos, you make this hard topics very easy to understand. Please, change the color balance of your camera from 'auto' to a fixed (hopefully calibrated) value. Thanks!

Outstanding explanations and schematic, very nice, try to explain in another video, boost pfc circuit.

Congratulations for 100K subs!

Excellent explanation!

Fantastic analysis. Thank you.

Beautiful ripple

My salute to you. Genius you are

You are great, perfect. always waiting for new video, please do some analysis in detail for your projects on the website specially induction heater and welder. Thanks

We want Q+A!!! 100k subscribers have been achieved!

You are a very good teacher. Thanks.

Awesome explanation. Thanks man!

Great video, number one on youtube for a good explanation on SMPS. would it be possible to change the output voltage from 24v to 100v or more if you modified the transformer windings and adjusted the voltage divider for the fed back, providing the caps and diode on the output are upgraded

Great explanation.

Hi, it would be very cool if you could try to build your own power supply of the various topologies, going simplest to more complex, showing your considerations in the design, and then building it to see how well it works. You could even take parts from other supplies so you built your own 'franken-supplies' :)

you have a very beautiful cat !!!

Exzellent, exzellent, exzellent! Zhis channel actually DOES, wat all zhe other elektronik channels like EEVblog etc. should do! I have zhis PSU and zhis iz exactly wat I vant to know! Very well done!

Why inductors (like You describe at 15:13) are not used after bridge rectifier capacitors? seems that it could help remove voltage ripple after rectification and filtration.

Wonderful and great work

Another amazing video!

Thank's for your upload this video. Very interesting, on GDT dead time can be passed.

this was very very informative, I guess half-bridge is not black magic anymore thanks

Awesome! Thanks, this helped me to identify the difference between the 12V and 24V model and alter mine into the 24V model. If anyone else want's to do this on the S-250-12 model, change R33 from 10K to 22K, and remove one of the two shunts to prevent over current at the higher voltage. Also if you just want to raise the voltage a bit, replace R33 with 12K and you then get 12V - 16.8V.

Great explanation on this subject! It happens that I'm fixing the 150W version of this very same power supply which is not regulating under load. After seeing your video, I adventured to use the same trick you did in order to see the waveforms on the power and base drive transformers. However, the pulse width at the base is just 7.2us max. I can see that yours is closer to 10us with 2.1A load. One thing that I found strange is that the pulse coming from the TL494's C1 pin gets a width of 15.3us, which goes to the base of its corresponding C1815 transistor driving the pulse transformer, and the pulse width at the collector of this very same transistor is just 7.2us with only 66 ohms. I wonder if this has something to do with this transformer maybe gone bad. Using just 100 ohms as a load kept both readings at same pulse width. Adding 200 ohms in parallel (with this 100 ohm resistor) caused the pulse to go the widest and output voltage fell from 24V to 20V. Could the magnetizing inductance in this pulse transformer have changed? Congrats on this great channel!!

I'm watching this while drinking Becherovka and digesting a Medovnik honey cake I ate five weeks ago :-). Wonderful explanation, I wonder if you could also show the noise in the output in some other video...

You, sir, are the hero I need.

very well explained

What an explanation! a real marathon! congratulations very alive, although, I am convinced, without the help of your cat you would not have done for sure! Lol Replace the aluminum of the main inductor should not make changes if you keep the same section and number of turns: you could only raise the maximum current bearable by the inductor (not the ouput current) Differently, if you change the number of turns you open a world of possibilities .... but in this case, the teacher is you! To the next video!

Waiting for part 3!

Awsome video. Thank you for sharing.👍👍👍

Great video. That's pretty strange with the output filter inductor. You say it may have been from a 12V supply. Maybe it was in a common mode choke configuration on the 12V supply? Then repurposed with the two sides paralleled to work with 5V, but if the inductor were being specified, it's not clear why they wouldn't just use one with a single winding... Anyway, your power supply knowledge is really impressive and it's amazing that you are making these videos rather than doing high-price consulting.

Very useful video. Thank you so much

Crazy good explanation, especially for DIY enthusiasts. What about making some custom multi-rail power supplies to power, for example, A316J IGBT driver optocoupler.

thanks for the great info sir, you make understanding everything so easy, i have one question how can we use it for charging lithium battery 54.6, it can just provide cc, we we disable current feed back somehow so that it gives constant current first and as battery voltage increases its current also drops ,regards, thanks in advance

Great video, love the cat transitions.

Your english is becaming better and better 👍👍👍

Amazing explanation about power supply as always, 👍👍👍👍👍, similar as pc atx supply

thank you very much. great content.

still eager to see the SMPS to Lab PS conversion ;-)

Best explanation...

Thanks, Great description Just two point: 1- I think two 1N4007 diodes (series with 10 ohm resistors) direction, is wrong. 2- Resistor 2.2 ohm in feedback path may protect TL494 from over voltage coming from positive rail, through 3.3nF ). But, for this reason 2.2 ohm is too low, may be it's value was higher, say 1K or 2.2K ohm.

You say you may do a video showing the conversion of this PS into a variable bench supply. I’d love to see that.

Regarding that arrangement error with the NTC thermistor, I think I've now seen the correct implementation of what they've apparently butchered-down: One of the old ATX power supplies I have, a Hipro HP-300SN (probably fairly "high-end" in 1998 when it was designed according to the PCB, though underwhelming by the standards of modern reviewers; now salvaged for parts), used a *pair* of NTC thermistors (each 2R5 nominal; it's common enough in other units to use just one such thermistor which I consider marginal on 230V) in the + and − terminals of the diode bridge; so that the 100~127V input range charges the capacitors through the 2.5Ω on their respective sides, while the 200~250V range charges the pair through the total 5Ω, thereby allowing a more forgiving compromise between maximum inrush and dissipation under load. So perhaps someone later copied such a design, then removed one thermistor without understanding the reason behind the arrangement.

Well explained. Love your cat and the dog

Where is the fan connector? Is it directly connected to output?