Tips on Repairing SMPS power supplies without published schematics. Learn about the half bridge configuration. My Electronics Course on Patreon, Link Here: / mrcarlsonslab
To learn more about electronics in a different and very effective way, and at the same time support this channel, go to Mr Carlson's Patreon page, click here: www.patreon.com/MrCarlsonsLab
hi, i like the switch mode powersupply videos, i was wondering if you could do a series, form the crappyest basic of a usb charger to adding protection, current reg, and other stuff.
Hi sir , can I know why the output voltage of the the SMPS Is high, it is not desired value. Example if desired value is 35 V , but it is coming 60V , what is problem in these SMPS
1. Этот модуль действующий. 2. Этот модуль движется. 3. Автор управляет этим модулем. 4. Гравитация подозрительно мала. 5. Скафандр почти не мешает записывать это видео 6. Название видео: "Монтаж smd компонентов в работающем оборудовании движущегося лунного модуля в открытом космосе паяльником Tesla, работающим на батарее Tesla, любезно предоставленном нам корпорацией Tesla. 7. Луна на самом деле не жёлтая, а красная. И летел этот модуль 300 дней. Наверное, это очень медленный модуль. 8. Борода делает ваш Скафандр теплее и уютнее.
My lunar lander did not take off.....Commonly called a divorce, as I lost my electronics shop in 2007 Well now it's 2022, and as iam single and starting over (in electronics that is) 👍 I know, sad.
Never seen anything like it. His first observation is the visual inspection with emphasis on build quality and quality components. Then the design engineering layout of the board. How he can identify immediately each subsystem and it's component and it's function. Then drawing the circuit and explaining the fundamentals from his intellectual mindset He was born to be a great teacher in electronics/electronic technology. Very few can explain or repair down to the component level. Keep up the great work !!
"If it does not work we will make it work" I love the confidence you show on problems. This was a very education video Paul. I always learn things from you. Like PLL circuits SMPS is another one of my weaknesses. Your hands on teaching method really helps. Thanks for another great video. Buddy
The Radio Shop you too huh. it took awhile for me to get my head around phase lock loops. but now i just picture a dog chasing its tail. lol ...theres a guy in the Philippines who offers a course on smps circuits. but from what ive seen mr c does a better job of explaining them. peace from Oklahoma city.
Well done, Paul! Great explanations. In the most simplest of terms, It could be stated the SMPS is the modern and sophisticated version of the old vibrators that supplied HV to auto radios in the 40's & 50's. Keep up the great work.
I'm hoping to see more repair videos. Gotta love your confidence you can identify and fix the issue -- power supplies always seem to die an early death.
7 лет назад
4:55 "If it doesn`t operate, we will make it operate, not a big deal" :)
Mr Carlson you are a reference of the very best on RU-vid. I expanded all the collapsed fields and saved to PDF to get a pure jewel of your comments/observations and those from all the viewers that also wrote brilliant and important comments/observations. It is a 73 pages PDF that I will read again and again for years to come.
well done and geared to someone like me with fair understanding needing refresher but have not toyed with some of this stuff in more than 15 years like they say """" if u don't use it u loose it """ am now at point in life i am hobbing in HHO GEN., power plant pulse and stabilizing power output from unstable supple v.. this gives me things 2 think on with other life experiences. ie: associate degree in computers & electronic, ham operator , service mechanic, hvacr tech, plumber , service tech n butcher in 3 packing houses, boiler tech . and "JACK OF ALL TRADES "BUT u no the rest. TY VERY GOOD
I can't say enough how well you are to explain complicated electronic devices with your easy to understand language and perfection, learning new things every times by watching about what was my specialty when I was younger.
GREAT job. At the plant, we used to just toss them. I have been a tech for 40 years now, 28 of them sitting on a bench repairing 2-way radios. Again, you are great at explaining and appreciate your videos.
Actually this is the best educational SMPS video for me. I have watched lots of them, they just talk and reading descriptions which you can find in datasheets or some papers easily. They dont describe every part of circuit just keep goin" this is the SPMS and it turns voltage yada yada yada...."
oh WOW.... what a lab... 11 seconds in and I had to pause the video to fathom in the amount of devices you have skilled over the time with your profession.
I really enjoy the way you approach all of your repairs for us common folk not in" the know" can still grasp the fundamentals being applied in actual applications. Thank you for spending what I'm sure is very valuable time to put this together. Have you ever worked on high frequency Inverter GTAW (TIG) Welders? Would you ever be interested in showing how one is repaired if so.
Awesome job on the basics of switch mode power supply operation! Just now came across all of your videos and thanks for taking the time to make them. I've been doing electronics repair my whole life and still learn something new every day.
I keep watching your videos. Now i could actually follow this video. From what i learned so far from you and what i knew, this video served another great lesson. I'm pretty glad I found you. Your a teacher I can follow and learn from. I will headed to Patreon and support you. Its only right. I gain so much from your videos.
The ONLY caution I would add to your Video is to NOT handle a Power Supply without FIRST discharging the CAPACITORS . ALWAYS assume they are charged. That was what we learned in the Navy... Just my $.02.
Great job! You are a great teacher. Well organized, great communication skills, knowledgeable and clear. Focused on the subject and to the point. It's always a pleasure to watch your videos. Congratulations!
WOW, I'm just learning on my own from RU-vid and books, on this sight with the explications you provide I can deal in my mind what to do and what not to do, in troubleshooting but I know I must be very careful to take my time a listen ,observe, and be patient, thank you young man for a better day in my life with your teachings. miguel
You're a really great teacher. Wish you'd been around Carleton University when I took Electrical Engineering there. :) I got my first oscilloscope when I was a kid. It was a World War II era Triumph I found at a garage sale, and I used it to repair the 1950s-1980s TV sets I would get at the curb. Being that the Triumph had only a two prong plug, it wasn't grounded, and I used to connect the stupid thing with reckless abandon everywhere in a TV chassis. What's the damper tube signal look like in a 1971 Admiral 21" delta-gun color TV? Let's find out! Looking back and realizing that the whole chassis and body of that oscilloscope was now live with B+ Boost, I cannot believe I didn't fry myself. But, in my defense, I did realize even as a child that electricity was to be highly respected, always used the one-hand-only rule, and never touched the two units at once. I learned the hard way about oscilloscope commons when I got a 1970s-era Phillips scope - which had a third prong. I connected the ground lead, turned on the set I was working on, there was a loud hum, and instantly the lights went out in my bedroom. It took a while to get the smell of burnt scope probe wire out of my bedroom. Thankfully, no other damage was done. In the early 1980s, lots of houses in Ottawa were having their furnaces converted to natural gas. Family friends gave me an oil furnace ignition transformer, with no idea how crazy-dangerous that thing was in a ten-year-old's hands. In fact, they didn't know what it was, they thought it was a motor - which itself would have been dangerous enough. When I made a little arc with it and heard the power of it, I unplugged it, and it became a toy to be operated only in the back yard with the distance of the lawn mower's extension cord between me and it. That was my own instinct, not every child is going to have that respect. I think I've had about three unintentional electric shocks in my life, amazingly nothing serious. One of them helpfully made my first car run better when it told me that my spark plug leads were shot. Most people aren't so lucky. Parents need to be alert to their kids working on electronics, whether they're TV sets or microwave ovens or guitar amplifiers or switching power supplies. Brushing against the horizontal output tube's anode cap on that old Admiral could have killed me instantly. I was afraid of electricity - still am, as much as I love it - and that has kept me safe. By all means, don't stifle the kid's interest in electricity. Remember that electricity is billions of times stronger than gravity and the fundamental force of nature that is right now keeping you from falling to the center of the Earth.
I will tell you my story....when I was 7 years old, the TV technicians that came to fix my old Phillips TV used to test the high voltage tube with a screwdriver producing an arc that for me was magical...I remember the TV tube failures because I keep asking questions that I think we're probably would not understand at that time. Once I was by myself trying to emulate what those techs used to do. My knoledge at that time was too litlle. I thought that the conector that is plugged to the tube probably was faulty and when I unplugged there was a gas inside the tube and was scaping due to the fact that I just unplugged. Well I put my finger on the hole so the "gas" should be stopped. Thank god the 120 volts was not connected. I received the 12000 volts discharge ....I couldn't move my arm, I was totally paralized by 30 seconds. I really thought that was the end. ... Conclution...if you happen to have a kid with curiosity about electronics teach him/her the danger things about it....today I am a happy electrical engineer that loves to mess with anything...I don't hate old tvs...as a matter of fact I admire the tube designers.... Mr. Carlson love your videos...keep doing them.....regards....
Another great video, helping me a little further forward with understanding how the SMPS works. Also a little closer to fixing my own SMPS without blowing me, my scope or it up! Thanks Mr Carlson.
THANK you for taking all that time to make this video. im the type that has to learn something every night before bed and im new to circuitry so this is amazing. keep up the great work
I often find it useful to just inject low voltage DC from a bench supply, instead of running full mains AC, while diagnosing a SMPS. That way you can safely check the switching and probe around as much as you like without having to be really careful.
That's what I'm trying to do,and as you said the brownout will kick in but you'll see some pulses before that, otherwise you can deactivated the protection since some ICs have a pin for that, or you can try injecting all the outputs not just the standby 5v.
Enjoying your well done videos and projects, thank you for the excellent quality, theory, testing, and techniques. There are a handful of providers doing this and you are one of those in the "Top Ten" in the world from my view.
I find electronics boring but what I do like is old technology. Watched one of Mr Carlson's videos and was impressed with his knowledge. So I watched another and another. Now I'm hooked. Nothing more satisfying then to watch someone who is extremely knowledgeable and good at what they do. His confidence that he'll fix whatever the problem is very impressive.
Another great video. The isolation transformer discussion was super enlightening. Recently I used an oscilloscope on a 1956 Admiral phono push pull amp that uses a power transformer. Figured I didn't need isolation. With the scope connection to the speaker (backwards) it created a hum. Even with the power switch off. I located a capacitor between the line and chassis ground caused it when the non polarized plug is inserted in reverse. Looks like isolation is good no matter what type of equipment is being tested. Thanks again.
Jesus - I so much love your Lessons - done not only with profound knowledge but calmly and comprehensive as well. Still (in terms of amount of Subscribers) very underrated channel.
Many thanks for your excellent tutorial. I was a TV technician 50 years ago, repairing tvs to component level. Then I moved up to Avionics tech job and later on to an aircraft engineer's job. I retired after 40 years without board level repairs. After retirement I find a pensioner's life extremely hard. I am refreshing my electronics knowledge to be able to repair TVs or Computers.Please keep up the good work. aftab ahmed. London
Awesome video. Simple and going slowly through whole build. The only thing that I would change is that when you are measuring, the camera could stay on the circuit and the some smaller screen on the measuring equipment or vice versa. (I did not have chance to watch rest of your videos when maybe you applied it already but for this video this is what I would love to see). I was looking long for just this simple step by step description on how the PSU is working. Thank you very much! It is now much more enjoyable to learn this stuff.
I have watched quite a few of your videos and I have learned alot from them. Even watched some that are over my head and still have learned from them. Thanks. I will continue watching.
Me again, Love what you do been doing. working my way through your videos. Learning, Learning, learning. Want to join your patron group but every dollar is tight right now. Please know that what your doing is appreciated !!! :)
Thanks Mr. Carlson for your gift of knowledge. How can anybody give this gentleman a thumbs down. When I was young, I had to ride my bike for miles to the public library (L.A.,CA.) and take notes after doing an extensive search for the correct information so I could use it in my guitar amp designs. I know that sounds like a joke but I'm serious. Learn what you can!!!
Good job for making this video. There are few people videos about SMPS, and most of them they are not explaining so good. Keep up the good work ! Thank you !
Probably the best explanation I've seen on youtube of what the transistors are doing within a circuit. I feel my understanding has made a quantum leap forward. Many thanks and certainly justifies my joining your patreon course.
Great video Paul, i like the inclusion of the oscilloscope. I recently got my first scope but not brave enough to use it fully yet, forgive the newbe question but could or should i use the scope on the same isolation transformer as the device under test? my area of concern is being tied to ground and frying something?
Noel Nestor - yea that is exactly what I was wondering. Would one require a second isolation transformer to float the scope? Although the scope manufacturers won't agree with that ...I would be grateful for advice on this as well. Love all the videos Paul.
Just for clarification i am using a rigol 1054z, so i think my options are using differential probes but thats expensive, using a maths function or running directly from a battery pack, i have tryed a 48v battery and it works but alot of hassle charging batteries
You isolate the circuit under test. Besides frying the scope you can fry yourself if you do not use an isolation transformer. With an isolation transformer in place: if you accidentally contact the "hot" wire, you will pull it to ground. However, if you contact both the "hot" and "neutral" wires at the same time, you are setting up a short circuit. -By putting your scope on the isolation transformer, with the circuit under test, you lose protection for the scope.- The ground on the scope will possibly be floating, unless you tie it to neutral. -- I was originally going to say the short-circuit risk described above is still present, but I don't think it is common to tie neutral directly to ground in equipment: that happens at the breaker panel. The scope may need proper grounding for safety reasons (to make sure stray voltages are not induced onto the chassis).
I suppose where I am getting stuck is by using an isolation transformer (as I do for the device under test), am I not just introducing a path to ground by probing with the ground clip? I'm learning at the minute and want to keep as safe environment as possible for me first of all and the scope also.
Noel Nestor You are introducing a path to ground, but the isolation transformer isolates the circuit under test from it's normal ground. That way, the rest of the circuit under test can "float" relative to ground. You still have to be careful due to the large voltages present.
21:35 "And you might even destroy yourself" Classic. I have been earthed. Sent to ground. The final fuse has gone away, it gives and gives, we could go all day ;)
My boss didn't like me to fix things like power supplies, "it's a waste of money". I did anyway, bought Solas for most new projects, never had to fix one, they are bricks. Excellent video, as usual. Kudos, and thank you.
Good Stuff! Great troubleshooting techniques and suggestions. Keep them coming. It would be great if you could do a video on low-cost tech gear, scopes and such that the 'average joe' could pick up to have 'on station' for [minor/medium-like] repairs. Also include how to operate them and such. I understand the limitations it could bring from it, but would be informative.
Hi Paul, Thank you so much for sharing. ...I have to say, that I find, the videos you make are more than excellent. Your tutorials, presented with your obvious and observable depth of knowledge, and delivered in such a calm and measured manner, makes watching them highly educational and thoroughly enjoyable. Thanks again.
Best explanation for half bridge smps on youtube excelent work.And one thing to remind that you forgot to explain how te feedback works so it can stay regulated,but overall great work.
I agree. I am especially interested, as a hobbyist with no formal training, on where you actually connect the probes when troubleshooting various components. Can you actually troubleshoot transistors with an oscilloscope? Where would you hook the probes?? Thanks
R Copo...... o-scopes are easy, its the spectrum /logic /network analyzers that’s tough, like looking at noise floors at -130db or beta gain of a transistor, when measuring the curve gets upsidown....yea buddy...and using the sig gens properly, its fun stuff....all good
Ten thumbs up! Excellent tutorial for working on 'hot chassis' circuits, which most modern consumer products are today. Floating grounds are the most commonly overlooked detail by techs today. (Afterall, who religiously uses, ever seen or even owns isolation transformers anymore? Those dissappeared with all the TV repair shops long ago) If that power cord isn't a 3-prong or is missing the ground pin ... big red flag, it's probably a hot-chassis design that can kill whenever the cover(s) are removed. A quick check with a battery-powered meter for AC voltage between the wall plug ground and the stuff you're working, can make all the difference.
That’s a curious warning about probing a live circuit without an isolating transformer. I just watched ElectroBOOM probe his industrial grade light sensor that was being powered directly from the mains and nothing went wrong whatsoever. 😇
the repair would follow a similar line BUT a lot of failures in comp supplies are dud caps (bulging tops) main cause of failure followed by complete blowup of choppers (not worth fixing) but do check the caps also the same on mother broads. many thousands of machines scrapped because of a bunch of cheap caps dying.
Konstantinos Nano should make power supply with u mechanical motor running gears for diffrent voltages a pma generator with all the voltages at the right rpm but charged from solar or wind to capacitors runnning 3 phase permanet magnets simple to fix with hardly having to know so much.
Really informed presenter here! Seems like a good opportunity to see if any true sign wave inverter explanation videos are posted to this channel.. The way I understand this circuit is that it's a pure square wave on the primary side out of the FET's. I'd love to see it taken one step further and understand how the bases are modulated in such a way to achieve "stepping" or better "true" sign waves. Thanks. And again, great video!
I wish I had never found your channel. I find myself watching your video's to all hours of the night and falling asleep in my computer chair. Although I originally came here to see if I could troubleshoot myself why my PC's corsair digital SMPS (AX1500I) at times goes into an infinite reboot, unless I turn off PS for some time (assuming discharging caps) and then restarting. I find myself watching being mesmerized by your knowledge. Sure wish I never dropped out of EE classes 41 years ago.
Very good presentation Mr. Carlson. You are truly an expert in the field of electronics. I'm a new viewer. Came on here trying to find out how to defeat the standby or sleep mode to flat screen power supplies. I am retired and have been making LED projects with scrap TV's that I've picked up on roadside! One of the projects is a LED shoplight, using the LED strips and the TV power supply from the scrapped TV's. All is well, very bright when using the diffusers from the TV''s. Only thing is, every 15 minutes or so, I have to use the remote to turn the light back on. It is pretty handy to have the remote. The question is, how to defeat the issue to the standby/sleep mode going into effect. I've read a lot over the past few months, many other folks are in the same predicament that I am. I would respectfully request that you would put on a presentation for this issue. I checked out your website (great!) but did not find anything related to my problem Excuse me if I somehow missed it and you have it. I'm babysitting grandkids - some distraction in the background. I'm still listening to the presentation above - wow, marvelous! Thanking you in advance for some help.
Awesome video. I like pausing when you show circuit diagrams and trying to figure out how it works, and then hearing your explanation afterwards. I will be checking out your Patreon courses, cheers.
I must have missed this one ,just watched it and what a brilliant explanation,im quite new at this and if you cant understand something you tend to put it to one side watching this has put my brain into 2nd gear, regards from across the pond 👍🇬🇧
Just very well done and absolutely great to have people share knowledge like this. There is life on the internet. Thank You, I am with joy going through your videos. Great job. / Patrik, Sweden
Couldn't they have simply driven the MOSFETs directly from the IC and saved some transistors and a transformer? The only catch is that they'd have to use 2 inverter gates (or even a 4N25 opto-isolator) at the IC outputs to provide a brief logic-high pulse to the gates, since the IC provides a brief logic-low.
No, there is about a 160 volt difference between the two gates. The transformer is required for that IC. You can get different switch mode ICs that can directly drive the mosfets though.
Well, there's also the issue of primary-to-secondary isolation (ie. between the mains side and the low-voltage side). Yes, there are also PWM controllers that are intended for use on the primary side, but even those would need some sort of gate-driver ICs (if we're talking half-bridge designs).
I assumed this to be the case but I'm glad someone asked the question so that a knowledgeable person could provide the affirmation. Following along as a layman, I had the same question as Mr. Squires.
@@AN-kg4ei Quality import. So the transformer had the screws loose and one fell off. But easy fix. Works fine. Hard to mess up a switch, transformer, and outlet.
as always very comprehensive and educating, now i only wish that Mr Carlson will make videos like this on other topologies also. Thank you for the effort.
Well explained, as always! Those "how not to's" are especially good :) This supply has an interesting secondary winding arrangement, not sure why they didn't make single winding of bigger cross-section. The reason might be a power dissipation, this way they shared it between the two rectifier packages; just my thought.
I'm coming to your channel late, Mr. Carlson. I wish I had discovered you sooner. I have troubleshot a couple of SMPS's and got lucky. Most of the time, I toss them and order a new one. It is nice to see how to troubleshoot them. :) Thanks for posting. :)
