> elec > électronique-de-puissance > eevblog-232-lab-power-supply-design-part-5-final-circuit-and-more-explainations

EEVblog #232 - Lab Power Supply Design Part 5

EEVblog - 2012-01-02

Dave goes through the final base schematic for his Open Hardware lab power supply design.
Schematic is here:

Amra - 2012-01-06

"Decided not to use the more expensive 10-turn potentiometers" Head = exploded.

No Bytes - 2017-04-20

Went from handy dandy to holy moly in less than one video.

Sebastian Scholle - 2017-02-25

The theory is really useful. Im glad dave went all the way with his design. So much to learn here.

Dark Angel - 2019-10-02


John Conrad - 2016-07-27

he is building a high precision instrument.  amazing.  Good job.  a good engineer sharing some of his capability and knowledge.Thanks a lot.

FDK - 2015-06-29

Wow, it became very complicated but I like it! It's very interesting to see how an expert would design these things.

Thilina Jayasingha - 2018-12-12

yes of cause!!!

Kryoclasm - 2012-01-09

Dave, I love this design! I would buy a kit when you have it finalized. Looking forward to the final videos. Keep up the great work and videos!

EEVblog - 2012-01-03

@DaemonPanda Yeah, considered that, and actually had it on an early draft with another LCD using novel mounting, but just went with a LED on the front panel instead. Free micro pins is an issue.

Skrapion - 2016-03-06

Man, I get the feeling there needs to be about 4 more videos between parts 4 and 5 in order to properly explore all this new stuff.

Pelle Reinke - 2013-10-29

A little note on the Microchip ADC. It does only have one ADC in it but the inputs are multiplexed, so the filtered search on DigiKey's site was correct :)

EEVblog - 2012-01-03

@MrP00f If so, sorry. I used a noise removal algorithm on this one to get rid of the fan conditioning noise. Artifacts of that?

zox012 - 2012-01-05

i love how this series ended up its awesome Dave! i was checking parts here in my country wouldn't cost over 12 euros without transformer "i love it" "beauty" :)

realcomix - 2012-01-03

you are amazing dave! when are you going to start your own company!

sabamacx - 2012-01-03

Absolutely magnificent Dave, you have outdone yourself!

EEVblog - 2012-01-03

@smithyduk I originally wanted a buzzer, but forgot to include it in the final design - Doh!

EEVblog - 2012-01-03

@DaemonPanda No, I use Chrome mostly. Opera had less clutter for the video.

EEVblog - 2012-01-07

@SigEpBlue @zega74 Yes, Altium. It's the package I've been using for 20+ years. I have not learned another package sufficiently yet. It's still an open design if Altium is used. What if I did it in Eagle like 90+ % of other "open" hardware designs? You'd have to actually pay $800 or so for the full package of Eagle just to do this size board.

EEVblog - 2012-01-07

@billysgeo The external ADC/ADC and uCurrent doesn't actually add a huge amount to the final BOM cost, you'd be surprised how much all the other stuff adds up to be.

EEVblog - 2012-01-03

@gxti Of course, so there is. Dave Fail.

Robert Gallop - 2012-01-03

Awesome again Dave!!!

EEVblog - 2012-01-03

@ultimatefang007 12bit resolution instead of 10bit.

Dan Casey - 2018-12-04

WAIT! You had an RGB backlight and you DIDNT program an awesome RGB backlight menu?!

EEVblog - 2012-01-03

@mm5032 Done.

Michael Montreuil - 2012-01-03

@EEVblog can you put up the schematic for download plz dave

Ashley Sommer - 2012-01-04

More PSU design vids please! I would love to see the board layout timelapse!

mj - 2012-01-03

@mathtek1 Altium Designer

TheLaidukas - 2012-01-03

Fantastic Dave!!! Waiting time laps of PCB design :)

DjViOd - 2012-01-03

Very nice, thanks for making the informative series Dave! I think I'll buy a kit when they're finished!

EEVblog - 2012-01-14

@Vlakpage The Microchip opamps only go to 6V max.

AnatoFIN - 2014-01-06

Doh, this series started so great as basic lab power supply, now this isn't anything like it anymore...

You really should have kept this high end stuff in separated video series.

Andrew Mackenzie - 2014-03-01

Basic supply was more or less taken care of in the first video, after that, it became an awesome PSU

technics6 - 2014-04-14

I agree. This is too fancy for 1A power supply.

fenclu - 2015-08-25

@AnatoFIN Actually, Dave stated from the very beginning that this was going to be a MCU-controlled power supply with constant current limit. He had to start with the basic analog part of the PSU, perhaps that's why you liked the first few videos. And except for the uCurrent part of the design all of the circuitry you see here is pretty much necessary for a decent MCU controlled power supply.

EEVblog - 2012-01-03

@starlino Didn't catch that one, I only found a 40pin DIP 24F chip I think. Will have to investigate, thanks.

sabamacx - 2012-01-03

@PonguigPeopinn Start from part 1!

Josef de Joanelli - 2012-01-05

@kildas Altium Designer

Josef de Joanelli - 2012-01-05

@zega74 Altium Designer

envisionelec - 2012-01-03

@tictourette I'm fairly certain he's aware of this. You know - as a professional design engineer. ;)

theonlyari - 2013-02-18

22:50 You dont have issues driving an ADC from an op-amp without a resistor to block capacitive loading?

zega74 - 2012-01-07

@EEVblog I was just kidding, give out gerbers at the end and you can lock it! I am also pretty novice in KICAD so i understand your reluctance, and also having access to such a nice peace of SW like Altium designer, i would not switch SW! Just make it at least 12 or 15 volts, 10 and some is such a odd value... Oh and adding function buttons (memories for preset programmable voltage values) are the best, try to implement that, I never liked fiddling on power supply pot. to fine tune Vo.

Nermash - 2012-01-03

That is some serious gilding of lilles:)

EEVblog - 2012-01-03

@g1fsh There is one more thing in the design people haven't seen yet...

Akmal MH - 2016-12-08

Wow... are those all 'sticker parts' ?

fuba44 - 2012-01-08

Hey Dave, first off im loving the project, and i can't wait to see how it turns out. I was thinking about the MOSFET on resistance, that needed to be under 1.25*10^-3 ohms, how about adding two MOSFETS in serial thus lowering the overall resistance, or atleast making it an option on the board, so it could be soldered in if needed. Well thats my 2 cents, all the best from denmark.

EEVblog - 2012-01-03

@snik2pl Yeah, I only just found that out. That limitation kinda sucks...

Gary g1fsh - 2012-01-02

Looks really nice Dave I love the 5 Volt USB chargeing output. You have allot of nice little tutches in this project "I LOVE IT" hahahahahaha

Josef de Joanelli - 2012-01-05

@ultimatefang007 He spent like 5 mins talking about that exact question. You should watch the entire video :)

Alec Hewitt - 2020-05-07

Thanks Dave

Tom Saunders - 2012-01-03

Great series, I'm planning to make my own version using an STM32 which has 12bit DAC/ADC with some cheap seven segment display modules

Aruna Rubasinghe - 2012-01-03


Always On - 2017-07-24

Can u make video about discussing working Class A audio power amplifier?

Greg Jaskiewicz - 2012-01-02


zega74 - 2012-01-05

@jmdejoanelli Altium, So much about "open" hardware...

silverstream314 - 2012-01-03

@DaemonPanda Or you could use it to indicate when the current limiter is activated, etc, which could be pretty neat.