EEVblog 1561 - uSupply USB Power Supply - Part 20 - Page 1
Forum section: electronics / general

author: EEVblog
author_rank: Unknown
timestamp: August 23, 2023, 11:00:01 pm
content: Part 20 of the uSupply USB power supply design. An update on where the project got to and why.A look at the finished unit, PCB and schematic.

author: rsjsouza
author_rank: Super Contributor
timestamp: August 23, 2023, 11:49:23 pm
content: I haven't watched it yet, but thanks for the follow up to this project...Certain projects are really subject to the tides of life...

author: SiliconWizard
author_rank: Super Contributor
timestamp: August 24, 2023, 12:35:27 am
content: Cool retrospective. I think many of us can relate to the story of this almost-a-product project.IMO the design was indeed too complex to make it a viable product for its intended audience (and thus corresponding price range) - including the firmware itself AFAIR. But quite a bit was learned along the way, with the custom LCD and custom transformer, how to implement USB PD, and more.But hey, third time's a charm. I think the next uSupply can be the one that you'll actually sell.

author: EEVblog
author_rank: Unknown
timestamp: August 24, 2023, 02:26:30 am
content: Strangely, this video has the biggest thumbs down ratio of all my recent videos except the LK99 one.Are people pissed off they can't buy it?, or don't like projects?I don't get it. It's my most requested video, and countless people cite the uSupply design series as one of the best things on my channel.

author: tocsa120ls
author_rank: Regular Contributor
timestamp: August 24, 2023, 05:36:22 am
content: Yea, she's gotten a bit old in the teeth, didn't she? Your first publication about this project is more than ten years ago I think.Interestingly, the thingIwould change is the custom LCD... make that either an e-Paper or even a color TFT, they are cheap now.You've mentioned open sourcing it but I can't find it on the 'official' github, is there a different one to github.com/eevblog?

author: EEVblog
author_rank: Unknown
timestamp: August 24, 2023, 12:37:11 pm
content: Quote from: tocsa120ls on August 24, 2023, 05:36:22 amSorry, gitlab:https://gitlab.com/eevblog

author: nctnico
author_rank: Super Contributor
timestamp: August 24, 2023, 01:32:38 pm
content: Quote from: EEVblog on August 24, 2023, 02:26:30 amMaybe it is because the video is about actual electronics design?IMHO it is a good recap of the project (judging from going through the video quickly) so I'm as surprised as you are.

author: pdenisowski
author_rank: Super Contributor
timestamp: August 24, 2023, 06:34:57 pm
content: Quote from: EEVblog on August 24, 2023, 02:26:30 amI've watched almost all of your videos (seriously) and I thought this one was one of the better ones. It's not easy making an accessible, easy to watch, and entertaining video on electronic design.

author: Nominal Animal
author_rank: Super Contributor
timestamp: August 24, 2023, 07:13:33 pm
content: Quote from: EEVblog on August 24, 2023, 02:26:30 amI loved the video.Especially the part about using a digipot (or alternatives like using DAC and opamps) for switchmode voltage (and current!) control definitely deserves its own video, if you ever feel like doing one. I mean, even hobbyists like myself can nowadays use TI Webench to get good suggestions on chips and circuits to use, but to adapt one for digital control is "black magic". (I only know enough to know that the loop size, actual bandwidth of the digipot or opamp, and capacitance and inductance in the feedback loop, will affect the stability and functioning of the switchmode controller.)A particular example I have, is to digitally adjust a boost controller from 5V to 7V-12V, to control three-pin voltage-controlled fans. (I've recently showed my PWM fan controller designs using ATtiny85, but I also have a bunch of pretty good 3-pin voltage-controlled ones with tachometer output.) The three-pin fans can be controlled by PWMing their 12V supply just fine, although one may need to adjust the frequency and add some filtering to avoid additional noise. The step-up-based one would allow efficient use of 5V USB wall-warts. (My ATtiny85 ones do not simply control the PWM or duty cycle based on user control; the user controls the fan RPM directly, with the ATtiny85 managing the duty cycle as needed, to get the fan to that speed. The purpose is to basically let the user control the airflow directly, even when the fan ages. Not a common need by any means, but very useful for the rare cases you do want/need one.)

author: SiliconWizard
author_rank: Super Contributor
timestamp: August 24, 2023, 10:37:56 pm
content: Quote from: EEVblog on August 24, 2023, 02:26:30 amWho knows. I'm guessing that many, seeing a new video about the uSupply, may have expected "good news" (ie.: finally making it to your store), and seeing it was "just" a retrospective with you definitely stating that it will never be a product as is, they may have reacted as spoiled kids not getting their toy.Likewise, during the (short-lived) "hype" on LK-99, many seemingly got pissed about anyone that would try debunking the thing, whatever you would actually say. It could be seen even on this forum.Quote from: EEVblog on August 24, 2023, 02:26:30 amYeah I don't know. I noticed that people seemed more inclined to be negative lately than they used to, on YT but not only.

author: nctnico
author_rank: Super Contributor
timestamp: August 24, 2023, 11:33:09 pm
content: Quote from: SiliconWizard on August 24, 2023, 10:37:56 pmThat is likely because people are fed up with the umpteenth nonsense debunking video from a creator trying to score cheap points.

author: EEVblog
author_rank: Unknown
timestamp: August 25, 2023, 01:10:34 am
content: Quote from: nctnico on August 24, 2023, 11:33:09 pmSo you think that demonstrably silly promotional video on their website didn't deserve to get called out?

author: rsjsouza
author_rank: Super Contributor
timestamp: August 25, 2023, 10:48:13 am
content: Quote from: EEVblog on August 25, 2023, 01:10:34 amI suspect that Nico is referring to the fact that *everyone* piled on the thing with flashy and catchy thumbnails and clickbait titles, which becomes somewhat tiring after a while (something similar to what is going on with LTT right now).

author: EEVblog
author_rank: Unknown
timestamp: August 25, 2023, 10:55:10 am
content: Quote from: rsjsouza on August 25, 2023, 10:48:13 amYeah, that's why I did something different. I wasn't going to make a video until I saw that demo video and laughed my arse off.I didn't see anyone else even mention it.

author: nctnico
author_rank: Super Contributor
timestamp: August 25, 2023, 12:55:51 pm
content: Quote from: rsjsouza on August 25, 2023, 10:48:13 amThat and there is so much nay-saying and negativity on Youtube already from self appointed 'experts' which go around with claims like 'if you have the tiniest bit of engineering knowledge, you can obviously see in 0.1 second that this system can never work' but fail to deliver a good analysis. It is just hyperbole piled on hyperbole like gossip magazines for women.

author: Rdx
author_rank: Contributor
timestamp: August 25, 2023, 03:39:29 pm
content: I am always suprised that project videos perform so poorly, but to be honest it probably makes sense that the usual tiktok kid can not maintain their focus for longer than some 60 seconds short clip.Does Youtube differentiate in their stats between performance amongst actual subsribers vs. random viewers? I would assume that less click-baity project videos might still perform reasonably amongst actual subscribers.I personally would love to see more project videos just like the usupply. It just gave a great overview of electronics design, pcb design, mechanical design considerations, custom lcd/keypad, and could have even more potential regarding UI/UX design etc.But I guess this is just not for the random folks on YTAnyway, love the work David 2 put into this. He seems to be a good engineer and totally got that engineering mindset that so many people in the industry are missing. 10/10

author: Rutger
author_rank: Regular Contributor
timestamp: August 25, 2023, 07:33:11 pm
content: I completly understand you don't want to sell the current design, it sounds like the BOM cost alone would push the unit in the $ 250 range.You really 'gilded the lily'Here is my suggestion what I would do if I would redesign this unit;1) Get ride of the display and touch pad, I know they are beautiful and functional, but you really don't need those you have your phone...2) Make it wifi enabled or (bluetooth if you think that is better)3) Get ride of the transformer4) Add battery function so it can run of that and use usb-c to charge and/or run the unit from5) Use an off the shelve heatsink6) use a wifi module with powerfull cpu's7) Use an off the shelve enclosure, I like the idea of the original designIn short keep it very simple and functional.Those are just my 2 cents, please don't take this personal.

author: Sniper1
author_rank: Regular Contributor
timestamp: August 27, 2023, 03:20:44 pm
content: DAVE here are a few design questions:1 why were 2 power elements used? aka why not limit current in the same FET as the current limitation?2 why is the SMPS only .5MHz ? you could get a way smaller one at 2MHz3 Was the custom heat sink truly needed? wouldn't a Al plate have down the job? Asking since cheap ish AL PCB could have done the trick .4* why are you still using such an old Altium version?

author: EEVblog
author_rank: Unknown
timestamp: August 28, 2023, 10:26:02 pm
content: Quote from: Sniper1 on August 27, 2023, 03:20:44 pm1. 2. Don't recall, sorry.3. Because it was cool, pun intended.4. I have AD23 installed. Accidently used AD17 which is also installed.

author: ejeffrey
author_rank: Super Contributor
timestamp: August 29, 2023, 01:58:25 am
content: Quote from: EEVblog on August 24, 2023, 02:26:30 amIt's more of a "how to not" video than a "how to" like the ones on designing a custom LCD. That's is probably harder to appreciate if you aren't actually in the business of making products and have experienced products that just never came together.

author: Brumby
author_rank: Unknown
timestamp: August 29, 2023, 03:07:20 am
content: Quote from: EEVblog on August 24, 2023, 02:26:30 amMy guess is that you've tantalised some people with a nerdy streak and then told them they can't have one.

author: SiliconWizard
author_rank: Super Contributor
timestamp: August 29, 2023, 04:21:32 am
content: Quote from: ejeffrey on August 29, 2023, 01:58:25 amYes, probably.Videos about failed projects are actually rather popular - that's a genre on YT - and some Youtubers even make almost exclusively such videos. But then they show a "spectacular" failure, so that entertains people.You know, a bit like acting like the EE clown.Here, that's not really a failed project - the project went to completion and works - at least technically. The failure part is more the story of a few questionable decisions and failed market, more of a management/marketing issue than a technical one per se, and even if Dave explains the points, it probably takes some knowledge and experience to even understand why the project didn't become a product.

author: EEVblog
author_rank: Unknown
timestamp: August 29, 2023, 04:56:47 am
content: Quote from: SiliconWizard on August 29, 2023, 04:21:32 amNot really, ultimately I just lost interest in it.

author: deepfryed
author_rank: Unknown
timestamp: August 29, 2023, 12:02:21 pm
content: It was a good video, I enjoyed watching it. I like project videos, fundamentals fridays, new part / datasheet deep dives, teardown / repair videos etc. It's what attracted me to your channel.

author: bitwelder
author_rank: Super Contributor
timestamp: August 30, 2023, 07:01:43 am
content: I did like the video, as it was a light talk about various 'engineering choices'.Even if the uSupply as it is won't see the light of day as final product, I think it could be an interesting base on more videos, e.g. about its evolution history (i.e. why some product changes) or how it could be optimized to potentially be further evolved to become a real product.

author: thm_w
author_rank: Super Contributor
timestamp: August 30, 2023, 09:51:14 pm
content: Curious about the dual FETs as well, originally I thought it would be for power dissipation but they are not used in that way. I'm sure there was some justification. Ultra-safe against overshoot maybe.Also with a tracking pre-regulator, might be able to get away with no heatsink at all.Not many negative youtube comments so hard to tell what people didn't like.

author: EEVblog
author_rank: Unknown
timestamp: August 30, 2023, 11:44:53 pm
content: Quote from: thm_w on August 30, 2023, 09:51:14 pmI don't recall. It might be in the design notes somewhere.

author: Nominal Animal
author_rank: Super Contributor
timestamp: August 31, 2023, 03:40:40 am
content: I do believe the reason for those downvotes are not in the video itself, but elsewhere; maybe something Dave has said on social media has riled up some activist types?One reason I still cannot post under my own name is situations like this: when you find out there is an issue/problem/unhappiness/negativity, but no way to find out exactly what or why. That still bugs me to no end. Using a pseudonym gives sufficient buffer for me to realize it's just online social pretend stuff, and move on; if it was real, somebody would describe it.

author: nctnico
author_rank: Super Contributor
timestamp: August 31, 2023, 11:27:52 am
content: Quote from: Nominal Animal on August 31, 2023, 03:40:40 amAsk yourself: who is the activist in the end? You for expressing your opinion or the people reacting to your opinion?

author: Nominal Animal
author_rank: Super Contributor
timestamp: August 31, 2023, 12:09:37 pm
content: Quote from: nctnico on August 31, 2023, 11:27:52 amAre you serious?Reacting to an opinion by downvoting a completely unrelated video by the same person, is a behaviour pattern that labels you an asshole.Ask yourself: Who is the asshole here?

author: RoGeorge
author_rank: Super Contributor
timestamp: August 31, 2023, 12:29:08 pm
content: On YouTube I see 1670 thumbs up and 69 down at 37000 views.No idea what the normal should be, but that ratio doesn't look bad to me.

author: nctnico
author_rank: Super Contributor
timestamp: August 31, 2023, 01:08:52 pm
content: Quote from: Nominal Animal on August 31, 2023, 12:09:37 pmYou are missing the point. I wasn't reacting to downvoting the video but to your statement that you are not going to share your opinion because people might react to it.About downvoting a video: who cares! Unconstructive criticism

author: SiliconWizard
author_rank: Super Contributor
timestamp: August 31, 2023, 09:04:56 pm
content: Quote from: Nominal Animal on August 31, 2023, 03:40:40 amI understand that, and it's all due to the very wide exposure we get on online social networks, something that's very new in our history and that we certainly have never had a chance to evolve to accomodate it yet (if we ever do.)People can get very negative and insulting - compared to what they would do "irl", sometimes as far as death threats - partly due, I think, to the disinhibition that comes with being behind a screen, and partly to the "mob" effect (if a few people start insulting someone online, then it is very likely to snowball). The mob effect has always existed, but obviously when the potential mobs go from a few/a few tens of people to potentially millions of them, this is a completely different story.With such large numbers, from a purely probabilistic POV, you're bound to run into a few people that just want to rip you apart for absolutely no reason. That's just probabilities.Thing is, online, many of us tend to act as though we had little to almost no inhibition, while inhibitions are what has made social interactions possible at all without society literally collapsing and everyone killing everyone else.Some people have no inhibition of this kind due to a damage in - I think - the frontal cortex. This usually makes people who act as though they had no morals and no limits. Horrific.The "virtual" nature of online interactions seems to trigger that to some degree.So anyway, I don't blame people for protecting themselves from that. It can be devastating.