HomeArticlesEEVblog #221 – Lab Power Supply Design – Part 1 EEVblog #221 – Lab Power Supply Design – Part 1 By Eric Benedict October 20, 2019 Articles, Blog 100 Comments Tags:arduino, atmel, avr, bench, build, circuit, comparator, concept, constant, Control, current, design, diy, do it yourself, Electronics, filter, fixed, hardware, how, it, lab, laboratory, linear, lm317, lt3080, measurement, microchip, microcontroller, modulation, opamp, open, oshw, pic, pot, power, pulse, pwm, regulator, resistor, schematic, shunt, software, source, supply, switching, technology, theory, transistor, variable, voltage, width, works Related Posts 30+ Kids Classroom Decoration Ideas 2019 Easy to Apply – Dilkash.pk 12 Super Cute Cake Decorating Design For Kid | Easy and Fun Cake Recipes | Tasty Cakes Tutorials The Weekender: “The Creativity Room” (Season 4, Episode 9) About Author admin 100 Comments Bogdan Serban April 4, 2016 How can you use this for a dual rail supply? And what if you want higher voltages and currents? Reply Benoît Vernier April 8, 2016 Doesn't the 1R resistor measure more current than what is actually used on the output? Reply Anjay V April 8, 2016 thanks to dave i finally understood how to set current with any micro controller. thank you so much dave!!! Reply Michael Michaels April 18, 2016 Why only 0 to 6V range? Why don't use 12V or higher? Reply Hagar76a May 26, 2016 Hi Dave. I'd like to know where the 10v is coming from at Vo (at 22:58) for the differential across the 1R. Is this the voltage input at IN? If so, does this mean you have to have a very stable known voltage here? Reply canal boat DIY May 30, 2016 can you help I have a PlayStation 4 I want to put on my boat but I don't want to use an inverter is it possible to make the PlayStation 12 volts or another method without using an inverter Reply Victor Rivarola June 7, 2016 You said that you can cascade 2 LM317s to get a constant current, constant voltage supply, and then went on to use complicated PWM stuff to control both by a uC. Can you make it simpler by using an MCP4231 chip (SPI controlled digital pot) or similar? Reply Victor Rivarola July 9, 2016 Why are 0 volts lower limit part of your requirements? Isn't that the same thing as shutting the supply off? Reply beppe3001 July 13, 2016 Thank you for the video. Really usefull !!! Reply Prabin Ojha July 14, 2016 And this is what you call ENGINEERING. Reply 4mb127 July 20, 2016 Oh man, I need more studying before I'm going to understand any of this. Reply Dicks X McIronCocke July 20, 2016 God I'm so happy you have a ATX to bench supply series, all these instructables ones look junky Reply Daniel's Game Vault July 30, 2016 Any way of bumping up the current limit higher than 1A ? I'm looking for something like 5A. Reply Dub Mona August 9, 2016 tap tap tap tap like the video tho. I did check sound card options for tap block. Reply wile richards August 12, 2016 Hey you know the difference between a yankee and dam yankee.one comes on vacation and leaves The other comes on vacation and gets mail box Reply red neck August 19, 2016 the current sense resistor knocks out all the voltage so the currant can't flow Reply Stuff Builder September 10, 2016 Thank you for the great explanation! Reply Airborne Works September 16, 2016 I am in need of developing a DC power supply that will power a 15.2 DCV 20A load at the end of a 150 foot cable is this something you can help me with I know AC power rather well but not very good with DC and you appear to know your stuff… Thanks Reply thaer shabo October 6, 2016 why we divide by 2 then multiple with 2 using the op-amp as a constant current ,can we used as a buffer without making it like negative feedback ? Q2: 32:18is it the diode limiting voltage important to make the op amp work correctly ,because it seems to be the current work side by side with voltage in ?the last config i hope to find answer and thank u any way Reply Murad Beybalaev October 20, 2016 Stop tapping everything all the time, please!https://youtu.be/tEVYsmpcbvk?t=8 You're overloading my irritation circuit. Reply Bobby Vincent October 24, 2016 what is the best video series for learning basic electronics building circuits etc. Do any of you have advice. Thanks for the great vids EEV Reply Vijaylaxmi Bhat November 1, 2016 Hi , I like ur lecture n tshirts too….I wanna have some tishirts like that:) Reply MrCrystan November 2, 2016 i really can't express how helpful and useful this tutorial series is! Thanks a million for describing in so much details, it's like a 2nd year uni stuff for someone who never did Electronics beyond college. Love it! Reply Kevin Miedema November 5, 2016 so you do need that buffer huh? whish I though of that earlier before I blew up my arduino… I got some LM350's discounted and im working on building some neat supplies with them. If you use AC as input its relatively easy to get a Dual-sided supply by tapping a higher voltage in the centre (say 60V if you want -30 ; 30V out) right? Reply Chrls5 November 6, 2016 Hahahahah speaking about power supplies, i have a question, i hope i'm not crazzy or anything, but can you all look at this manual http://www.ti.com/lit/ds/symlink/tl494.pdf page 14, bridge rectifier looks ok, but it is in my mind a trap for young players! hahaha anyways, check it out, let me know what you all think about this. Reply Philip-Jordan Fadriquela November 23, 2016 Could you make a follow up video but with a switching power supply, buck/boost converter. Also it would be interesting to see a dual rail power supply. Reply robviolin1 November 26, 2016 could you please do a review of the different dc power supplies on the market for us dummies? thanks Reply sholimz November 30, 2016 like your tee shirt….. Reply Duy Nguyen Tran Cong December 12, 2016 very valuable video, help me so much in power electronic class =))) Reply John Michael Stock December 30, 2016 If I use the LM317 as a CC circuit on an ALREADY regulated power supply, when I change the CC value, will it screw with the output voltage? Reply Ryan Grondin December 31, 2016 What is a good power supply to start with? Reply Will noneya January 4, 2017 I appreciate all the help you have given me on my path to engineering. You are a great teacher. Reply humam Ramadan February 12, 2017 please can someone answer me '^' on minute 36:40 what is going to happen when the i set is bigger than the measured value of current on the shunt resistor Reply Bobbeh Mcstuffinshire February 20, 2017 Hopefully sometime this year I will understand this. Reply Kinte Ryder February 22, 2017 dave i realy like your videos :D:D:D:D:D:D:D:D Reply gourav kumar February 24, 2017 I designed a 24V DC to 3.3V DC using LM1085 and a 10uF capacitor , i was getting 3.3V , but when i give this 3.3V into ESP8266 it worked for few minutes and get burn out …… Why? Reply Eugene Zagidullin March 14, 2017 I think comparator can oscillate in this configuration Reply Reeko Azil March 18, 2017 Bingooo !!! Reply shreyans baid April 10, 2017 can u help me in designing a high voltage dc power supply. Reply lee rr April 14, 2017 That's very helpful to me. Reply Oscar Casarroja April 15, 2017 I love your 555 T-shirt Reply 0000000rel April 22, 2017 This is great! Thank you for making these very honest detailed design tutorials. Reply Florea Alexandru April 25, 2017 hi, i want 5A curent output, i put 5 lt in paralel, but the Iset will be the same? 0-1V? Reply Benjamin Soto May 1, 2017 where did you get your t-shirt? 😂 Reply William May 15, 2017 Why do you need 0 volts Reply Brice Johnson May 21, 2017 at 7:40, if you feed the reference -1.25 volts, will the regulator output 0 volts? Reply joe taouk June 13, 2017 hi thank you for your excellent video can i use TIP3055 to gain more current also min load is 0.7 Reply Sebastian Scholle June 21, 2017 You went from explaining how to replace the CC 317 part with a discrete Opamp and Darlington, then you just shoved that into the CV part of the circuit!I'm not sure sure how the Op Amp/Darlington will control the voltage. That seems like a Current Controller only, I think my current knowledge limits me to understand this properly. Can anyone explain? Reply Paulo Constantino July 7, 2017 27:14 : just make sure………….. ooops Reply Dylan Tomberlin July 29, 2017 What's an application for 0V? Reply naren ramasamy August 5, 2017 hi..sir can it be used to charge a Ni -MH battery?? thank u… Reply Jemima Khan August 14, 2017 in 5 years from now, I hope to design circuits like you do 🙂 Reply PirateKitty August 23, 2017 Be aware that this project, like so many others, has been abandoned and is incomplete. So if you are planing to build one, take that into account. Reply Ella Banana September 13, 2017 19:00 So I've gone and made that constant voltage circuit, and immediately had the exact issues you were talking about. I'm using a single NPN power transistor instead of a Darlington pair, but other than that it is effectively the same. My problem is that, while I can handle the logic and math of these things no problem, when it comes to dealing with the more complicated parts of dealing with characteristics of different voltages and resistances and crap that is where my knowledge falls apart. Reply Danny Sebahar September 19, 2017 I assume the various idioms he uses are Australian things, but he could just be fucking with us. "Bob's Your Uncle", "Dog's Breakfast"…What the hel does any of this mean and where did it come from. Reply Mudaser Awan September 30, 2017 I dont understand how we get 5.5V across the output voltage divider when we supply 1V from the bottom opam? Reply Berkehan Kutluata November 5, 2017 abi sen niye böyle konuşuyon yah afewuufhawfşıoaghwawıaesgh Reply Pete Shannon November 12, 2017 You have to study several years in electronic engineering so you can figure out the most complicated way of making output voltage the same as input voltage? Reply SIgnal Circuits November 15, 2017 HI, I am trying to do the same circuit as 10:00, however, my output voltage stays in 6.3 volts. Note I am using lm338T Reply OVERLORD December 7, 2017 Dave, I love you man… but please, I beg you… please stop tapping the whiteboard with the damn pen!!! Reply Ben Leadholm January 12, 2018 "It's going to be a dog's breakfast…" LOL we never hear that in Minnesota. Reply ben amed January 18, 2018 i wonder if ucan help me please, here i have esab mig U4000i multi-process machine but now i dont have the wire feeder (esab origo feed 3004) which got the panel control (origo MA23 or MA24 )so i can no longer use this machine without a wire feeder even for stick welding , i was wondering some how i can modify this machine so i can use for cc welding like buy a PMW controller and connect it to the driver gate board or something like that ? but not sure from where to start , can anybody help please , i will leave below a link for the manual and wiring diagrams etc.. http://svarka.rv.ua/image/Sweden/Mig,Tig, Arc,U4000/Mig,Tig, Arc,U4000-S-new.pdf Reply Rumen Markoff February 7, 2018 Good Drummer Reply Fried Mule February 14, 2018 9:00 Lol do only work with electronic, not hammers! 🙂 Reply Scott Burr February 15, 2018 Only just watched this video and really enjoyed it Dave. I've always been fascinated by test equipment and power supplies especially. I've designed switched modes for a living but never got round to designing a decent bench power supply for myself. this might be the inspiration I need, off to watch part 2!! Reply sanket thakur February 25, 2018 Can i use same circuit for my benchpower power supply which may be ranges from 0-28 volt with 3A of current?? Is there any problem with such high voltage?? And you doing really good.. Thank you for such brief explanation.. Reply SHIVA KUMAR RAO February 26, 2018 Dave can you please explain the internal circuit of pwm ic 3844… Reply Mart C February 28, 2018 Great videos Reply Dylan Kirdahy April 1, 2018 Fantastic video! Thank you, Dave Reply andro meda April 7, 2018 Hi Dave, great video! What do you think the product multi channel power controller from nicslab? www.nicslab.com Reply ThinkLearnSolve April 8, 2018 the 5.5V doesn't make sense, should it be 4.5V? 25:42 Reply Ausprobieren Dann Weisst du es April 28, 2018 Thanks very much for this circuit, this is one of most important circuits for me Reply Rob Krimm April 30, 2018 Double Like! Reply Mainkordor Mawblei May 2, 2018 i felt joy a nd knowledgeable at the same time Reply ThinkLearnSolve May 4, 2018 wow, I finally understood what that voltage inserted at the bottom via the voltage buffer does 🙂 22:51 Reply Hari harank May 21, 2018 Why LT3080 why not LM317? Reply Matthew Peterson May 23, 2018 gosh, the tapping, dave… the tapping…. Reply Tennis June 18, 2018 Squeaky voice Reply Rahul Kumar July 6, 2018 Great work. Reply Divanilson lopes July 15, 2018 muito bom os seus videos queria fazer uma fonte através dos seus videos mais não entendo inglês e a tradução por legenda não e muito boa não consigo entender não Reply Divanilson lopes July 15, 2018 você tem sem ser em video esse passo a passo Reply rodmongodwood July 31, 2018 are u drawing ur GND points like Earth point for a reason or just to mess with us? ^^ Reply Хлебников Денис August 19, 2018 🙁 tooooooooooooo complicated Reply CreditDebitCards CostYouMoney August 21, 2018 I like the Tee shirt he's wearing……I want one. Reply Kenlong haloGEn September 25, 2018 what darlington transistors and op amp can i use for a 100V 10A voltage regulator? I'm trying to cook a high power voltage source for power amplifier repairs 🙂 Reply joshua43214 September 29, 2018 We are going to use this part cause it is awesome. <10 minutes later> This other part is better. <28 minutes in> We won't use the awesome part at all because this other part is even more awesome. <30 min in> We are going to dump one of the more awesome parts in favor of a bunch of smaller parts. Reply sara patil October 3, 2018 Thanks for sharing the videoXitij Instrument is one of the best leading Manufacturer, Wholesaler, Trader, Retailer, Service Provider of all types of Agarose Gel Unit in Pune, Maharashtra, India. Best Agarose Gel Unit supplier in Indiaagarose gel unithttps://xitij.co.in/product/Agarose-Gel-Unit Reply Ray October 18, 2018 Hi Dave I'm getting back into electronics after at least 30 yrs. I can't begin to tell you how useful and informative this and the follow up videos have been. thank you so much please please do more of this type of design videos Reply G. Com November 5, 2018 You look like my driving instructor from 16 years ago. Uncanny. But cool 😀 Reply Michael McDonald January 3, 2019 I know this video is 4 years old, but I really am having a hard time filtering PWM to anything resembling a constant voltage. Anyone want to help? I have 100hz coming out of a 555 and I want to smooth it. Not to control anything specific. I just want to know how to design a filter like that. Reply FalcoGer February 16, 2019 0V, pull the plug. done.So you wanna set your power supply to with 0-10V. so you need to put on a voltage of 0-10V… Something seems recursive there. I guess you could use a potentiometer to split some voltage, but then again, where do you get that voltage from and make sure it's stable??Also how does PWM make a stable output? wouldn't the amplifier try to match the input voltage, alternating between 0 and x? Reply Thomas Lanik March 31, 2019 Very nice, Dave. BTW, I easily found the TI Data Sheet for this device and it has great info and application info that supports and supplements (dare I say compliments!) your friendly tutorial presentation with other benefits. Excellent! Cheers, mate. Reply t md April 1, 2019 What about using a 1.25V zener in reverse on the adjust pin? I think I have seen this done before to get an almost zero volt output. Reply Chimera April 9, 2019 This video is great, but the trapping is driving me nuts! Lol thank you for the amazing content, and thank you for teaching a person who is learning to solder, and build electronics on their own! Reply Yasith Gamage April 10, 2019 you posted this in 2011 and still this is like the best video that explains how to make a power supply design ! thanks very much for this ! Reply Dave G April 12, 2019 Jeez Dave, swapping the breadboard colors is really messing with my head. Reply Eva Liu April 23, 2019 Nice video! Found another passage about this, welcome check: https://www.raypcb.com/pcb-power-supply-design/ Reply Nepetalactone June 17, 2019 Every time the guy tap the white board with its pen, drink. Reply Ewoud Wijnstra July 6, 2019 Well if you provided a beginner friendly explanation people could ectually use this. You talked for more as a half an hour but still didnt learn a thing since your explanation isnt clear at all why isi it this circuit. What about mains voltage There isnt a eord about what goes in since you use a second bench supply so what is the point if this?? Reply Yosory August 7, 2019 You're breathtaking.After all these years Reply Add a Comment Cancel reply Your email address will not be published. Required fields are marked *Comment:*Name:* Email Address:* Save my name, email, and website in this browser for the next time I comment.