@@TRXLab Also wanted to thank you for your videos; very helpful. If I could just offer one criticism, it's that your pronunciation of 'weight' to the native English speaker is wrong, and my brain gets stuck for awhile (until it adjusts!); I then have to go back aways and re-listen. Kind of like when you're reading and you come across a word you don't know the definition of. You can keep reading for several pages before you realize you haven't comprehended a thing since the errant word... Anyhow, just trying to help; thanks again! FYI, 'weight' is pronounced the same as 'wait'.
A special thank you Peter for all your videos and all the time spent in doing them. I have expertise in software for 30 years but normally don't get to experience electronics and in the good video representation you can do it in. I want to let you and everyone know that you have made a difference in my understandings and on a business perspective a more dangerous competitor. (Not against you of course).Peter you will see a similar message to Paul but I am glad to present you two are the Best of the Best.('Besten der besten')
+Ham4Ham Hi John, thank you very much for the kind word and for the honour! Always happy if my videos of any need! So again thank you so much 73 and the best
One of the BEST way to make even layman to understand. Hats - off. I really enjoy your pronunciation of each word with a tinge German accent. Vielen Danke. Auf wiedersehen.
Switching Power Supplies with Simplified Understanding of its working principal in theory supported with practical demonstration. Great video for hobbyist and seasoned home-brewers as well as for anyone interested in an electronic engineering.
One of the greatest video i have watched in my life ....it has clarified everything .....couldnt understand until i saw this video....thank you very much
Thank you so very much for making this video, I've been trying to get to grips with SMPS for some time, I have seen other videos on you tube, but this is easily the best. And you explained it in quite a lot of detail, getting all this technical information across and at the same time translating it into English without so much as a mistake, Sir I salute you , You have done an excellent job !!! Ray H. ( from the U.K. )
G'day Peter, when you were talking about the U802 cnx82a Optocoupler and the way you explained it. Well done, seeing your Engish is your second language. The last part about the common mode filter this is a real part of QRM on our ham channels. Thank you Peter for sharing these moments with you. God bless you and your family.
+Dennis Peake Hi Dennis. thanks for the nice feed-back! Well my English could be a bit better but may get better over the time:^) God bless you Dennis!
Einfach clever! Best professional explanation, full of competence special the way you try to share your valuable professional knowledge and long years experience is clear to understand. Keep doing it. You are wished the best too.
Nice lesson on the basics of the SMPS's, Peter. Even though I've been learning about them a few years, I still enjoy watching you explain about them. And thanks for mentioning the grounding issues to help keep people that are newer to electronics from blowing their scopes, or worse.
Excellent video, very informative, having worked on various switching power supplies my self I sort of had an idea how they work but never really took the time to delve into them too much, when you are trained to do one job such as setting them up and testing them on a jig I dont think you ever get to appreciate the actual idea of how they work....And yes it is very easy to get a nasty electic shock from one as I have found out on numerous occasions..LOL....Fantastic....Keep up the great vids....73 from the U.K...
It was a wonderfull n extremely comprehensive explaination of more than the basic working of SMPSs by the very intelligent gentleman although his english was good enough to follow (i think he being a german) it was very clear n highly informative !! A big Thank You to the gentleman !!
ShOcK & AWE clarity. A lesson that will, I'm sure, will be taught 500 years from now. p.s. That 1K 5 Watt resistor seems strangely out of place in a "efficient power supply". But I use to believe that the Electron was a super hero from the 50's. Thank you for the video. You RoCk!
A very clear, well structured presentation, sincerely thank you very much for your generous contribution. I had an unclear idea about this topic but now its totally clear to my. As far as I know the modern welder machines are based on this same principle and I would ask you if possible a video of this theme. Greetings from México.
I love the video and the content. It is very useful information. I am amazed that you have the schematic and the datasheet for your power supply! The ones I salvage are very hard to find any information on. Thank you very much for taking the time to make it.
If you do work with weak signal RF with any kind of A to D sampling, you'll want one of those "old school" linear power supplies to eliminate the hefty RF noise generated by most switching power supplies!!
Higher frequency was used in planes with 440Hz, even before switching power supplies to make them much lighter. Of course switchinh power supplies go WAY BEYOND 440Hz, making them tiny for the power they control! Good video, thank you :)
I am so glad you are on RU-vid. There are almost no people who understand anything anymore. Bless you. The Arduino cancer has destroyed the minds of so many young people, I sometimes fear for our future. Please keep a clear signal on this band. You are one star in the night they can follow.
Thank you for sharing your intelligence with understanding SMPS. Your video has helped me further my life long ambition of understanding electronics. If I can keep this intellect in my mind and make a career, I'll share my success with you or your family. With great affection. ACT Cell.
hi, that's awesome video. suggestion for improvement: you can use two video camera to shoot at two different portion. also, in this video, you should slowly increase your load side, and monitor the zener diode output, and thus monitor the oscillator circuit. i know i'm too demanding, but it make clearer understanding. Thanks a million for this wonderful video.
Peter thanks for the video...I never knew how those supply worked.I still prefer my linear PSU i have heard some horror stories with Chinese Switch Modes using poor components.Your right lots of radio people complain about the noise generated from these but lets face it,they are in everything these days.No thanks i will try keep my 20 year psu's going as long as i can.
+charlieoscar09 Hi, yes right there are some lousy products on the market which are causing more trouble than anything else...I like my linear psu as well especially because it is do silent without a annoying fan.. Thanks for watching 73
Hello Peter, good general information about the working of the switching mode power supply. Maybe it would be nice to see how good the common choke works. Many hams suffer from the solar panels converters. Many thanks and catch you next time.
+FEY Hi, yes you are totally right but unfortunately I have no artificial mains network which is needed to locate and show these noise and qualify it. But anyway I'm planing to have one in the future.. 73
Thank-you for the video. Please can you explain to me if the 320V at the collector of the chopper transistor in the primary circuit, gets drained to ground through the emitter at a rate of 70KHz. This will then create a continually growing and collapsing oscillation of magnetic flux in the primary transformer coil? Is the 5W resistor connected in series with the emitter to ground to handle the heat being dissipated by this process. I need to get a clear understanding of how the chopper circuit works. Thank-you
Hi , you have made a great job by explaining how works SMPS theoretically and practically . Can you make a complement video ? by simulating what can happen with the SMPS when for example according to your schematic: 1- UC3842 is not getting power supply 2- the transistor in the primary side get short circuit 3-the optocouplor is dead 4-one or some transistor in the secondary side get short circuit 5- rectifers diode in in the secondary side get short circuit.............ect the idea for every case will be to show in the oscilloscope or voltmeter what you are getting in the test point of the schematic. thank
+Henzer zak Hi Henzer, thanks for feed-back! Well very good proposal on the different scenarios..Unfortunately I have no capacity to do this video, sorry for not having a better answer for now. May be possible in the future.. All the best Cheers.
Nice overview Peter. As you know some early SMPS had problems with noise; later designs allowed for "tuning" (or moving) any spurious outputs that fell in the ham bands. I'm wondering if the can on the right side of the PCB might have some of that tuning function circuitry inside to clean up the output side of the supply? I was floored when I got my first SMPS when I compared it to several linear style Astron's here in the shack - amazing difference in weight as you point out. Thanks again! 73 - Dino KL0S
+Dino Papas Hi Dino, yes early SMPS's and in particular all the cheap designed units with crappy components and without good common mode filter and proper shielding. No in the can is only the main power transistor shielded without any compensation components. The featured product is nothing special a very cheap and crappy sat receiver psu so nothing special to expect. Thanks for comment! 73
Well done...I've seen some kind of SWM power supply with transistor instead of IC oscillator and .how could feedback by photocuppler work with that transistor?
Something basic is confusing me - why the width of the pulse matters, as the transformer's primary magnetic field only expands/collapses as the voltage changes (on the rise and fall of the pulse). Since the pulse is basically a square wave, does the magnetic field need the time of the wider pulse to fully expand? A high frequency square pulse must have very different physics through a transformer - as compared to 50-60 cycle AC. Thanks, hopefully a short "simple" answer is possible. Excellent video by the way - I enjoyed it at 1x speed.
Thank you so much . I have a question . If I do not find the volts on the cathode of TL431 What will the malfunction be? Is the transformer vulnerable to damage or malfunction?
+ayman zayed Hi Ayman, thanks for watching! In my video #80 you get some more information about the oscillator IC as well. But basicly it is simply the oscillator with some protection functions around simply switching off the oscillation.. All the best 73
What’s wrong if it breaks down if normal load is applied? Example it works until about 3 or 5 volt output then it begins to bump (on-off). Variable output from 3 volt to 15 volt.
Thanks for the nice video! .. I always like a new perspective on SMPS circuits .. maybe you can explain more about the Power Factor Correction section of a more advanced power supply sometime? I have always wondered about the details of those
Peter what about your workshop safety I.E you mentioned and isolation transformer? I will also be doing work re-capping some old valve equipment thanks
+charlieoscar09 Hi, will try to get something together. Especially if you work with valves it is essential to work with a certified safety isolation transformer. I presume you have seen Paul's video on that ? ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-XBsQ3sZ45Fk.html
+Ajay Rao Hi Ajay, yes that is important or you can use a differential scope probe both is possible. Be careful with the both different ground sections. Thanks for stopping by. Cheers.
What's going on with the mutual inductance TB01? Is that for line isolation, to avoid ground faulting when connecting a case ground to the circuit ground? Do have any idea how to analyze that part of the unit? How much inductance is needed for reliable isolation? Any idea where I can find a tutorial on this aspect of the circuit?
great vid. one thing im still confused about though is why does high frequency through the transformer mean a 4 kw load can have such a small transformer-its still got to carry the current of 100 + amps at a low voltage to achieve that wattage-how can it all go through a tiny transformer without it getting hot?
I am a little bit confused on the function of the opto-isolator/coupler. If I am understanding this correctly, it provides a means for feedback to the IC in order to tell it to increase/decrease the PWM duty cycle, which switches the transistor controlling the the transformer? Does it essentially join the primary to the secondary side without a physical connection? There must be programmed logic built into the IC which keeps the output voltage the same regardless of the load? Would it be possible to incorporate a variable resistor coupled to the IC to control the output voltage level? Sorry for all the questions, but I am trying to wrap my head around the concept of a switching mode power supply.
Brandon C no, the optocoupler circuit completely shutdowns the IC output. When the phototransiter conducts it passes the 5V ref voltage to the error circuit in the IC which dumps the output to pin 8 by a 15kohm resistor according to the data sheet
Hi Michael, well that would be something for another video. But in short it is all due physics in the core material, sorry to complex can't be answered with a few sentence ...Cheers
Awesome video, greatly explain. I just have one question what's going on on the feedback circuit add the adjustable ziner diode with the resisters and caps that are attach to the circuit?
nice work, the protection circuit in my analysis is explained backwards, the optocopler is off state in normal state, the optocopler is switched on when in protection mode, can you check test pin 2 again thanks again, i really like your videos
quick question if I may. is it OK to have the power supply and the oscilloscope on the same iso transformer, but different outlets? Or, do you need to have 2 distinctly separate is xfmrs?Thanks!
thank you so much, the outlets on my wp-30 are isolated from each other. last question, being as you are so generous with me..I have a current limiter (light bulb on an outlet as per uncle doug) can I : plug my device under test into the current limiter, and plug the limiter into the iso xfmr, that way I know if there;s a hard short (bulb lights)AND the mains of everything are isolated. Thanks again!
