Hi. Here's a do-it-yourself power supply that you can build for about 20 25 bucks maybe and you can do it in about like 30 minutes which is what it took me to build this one. It works on an external plug pack of any voltage and I just build it into a case that I had lying around, had some binding posts lying around and it's a little. Cute little bench power supply and it can do 0 to 20 volts, output, up to 0 to 2 amps, constant current and constant voltage.

and it's got this neat display here that basically shows you all the current and output power and the interface. here. a nice little multi-line LCD that shows the set voltage, the output voltage, the set current, the output current, and the power and some preset voltages. There's an on/off button here which is not on its output.

Odd off there. we've got ourselves a selection knob and if we switch it on here, it's got constant. We see we're in constant voltage mode and we're got an output voltage of 5 volts and output of not 0.99 amps and that matches our load up here precisely. Beauty.

So how do you build one of these puppies for like 20 odd dollars and building in 30 minutes? Well, you might have guessed that this module is a complete off-the-shelf module. This is not a kit. I'll open it up and show you that there's virtually nothing in here except Tada. This little module here that you can buy on eBay Aliexpress or whoever not.

actually sure who manufactures this, but it's a very cute little module that we'll take a look at an is basically just the external DC in and the output. It's all self-contained but some company designs and manufactures a complete range of these was a whole different bunch of voltage and current and power output capabilities and you can like I Found a price of one of this module in particular, the 20 volt R2 amp one was like 17 US dollars on ebay delivered and that's your entire bench power supply. It's ridiculous. So the one we've got here is here's the manual that comes with it.

It's in Chinese or English Here it's the DP 20 V 2 amp module and this is a 4.5 to 23 volt input which is great so you could actually power it from a USB you know power bank if you want to any USB thing you want to do I Haven't tried it that low yet, but I've just using a 12 volt our 3 amp plug pack. but basically you can throw any plug pack I Mean if you haven't got a whole bunch of spare plug packs sitting around from old laptops or any old gear or whatever, then well, you're not really trying. So yeah, you don't have to buy anything else. just the module and a couple of binding posts and a DC jack and that's basically it - 0 to 20 volts output is 0 to 2 amps maximum 40 watts I am doubting that I haven't actually tested it yet, but I am very much down in specs aren't going to set the world on fire in terms of peak to peak ripple.

it's a switching converter. Of course it's not a linear converter, but hey, for for 20 bucks like you can't complain. This thing's great. and if you're not a fan of the real tiny display down here, you can get other ones that like this one.

I could actually pair it up. This is it. From that you note the same anonymous designer manufacturer, whoever it is, if I find out who it is, I'll link it in down below. but this is our input voltage range 6 to our 40 volts.

It's got a larger, you know, a better-looking display like this and this one is a higher power device. We've got a larger heatsink I'll show you the other one that I'm using. but yeah, this is a higher power job, but basically voltage in voltage out completely self-contained These modules are fantastic. This one might be a little bit more expensive, but yep, just choose your flavor.

And here's another one. It's the DPS 3 double O 3 and adjustably not not point O one volt steps for 240 volts. This one uses SMD parts. The other one was kind of a through-hole so if you there we go compare those two so they're just available in all sorts of different versions.

This one looks to be a little bit more high-power bigger inductor, bigger heatsink, bigger power. This uses SMD ones, but even this one is very nice. They claim an output power range of 96 of watts. Well yeah, good luck.

96 watts out of this output power because I haven't measured the efficiency of this thing at all. But if you like assume like it's really fantastic at like 90 percent over the range for example, then if you're delivering let's say in the order of a hundred watts to your load, then this thing has to dissipate 10 watts. And well, that's just not going to happen on a heatsink of that size with no airflow. but you can see that this one here can I do 0 to 3 & 0 to 32 volts in 10 millivolts, 0 to 3 amps in 1 milliamp steps and it's got one milliamp resolution whereas the one I just worked in the case here is only 100 millivolts resolution on the voltage and 10 millivolts resolution on the current which is okay.

And here's a look inside and well, it's a bit how you're doing some of those joints. It looks pretty crusty, but hey, what do you want for the money? Like it's kind of kind of sort of do the job Me and Bingo just in a minute I changed my supply over to the DPS three double O three supply. is that the designer and no, that's so I don't know what that symbol is. Anyway, that's the model number and we've got a much larger, colorful display here.

Very, very nice now. I'm going to admit that the user interface on these is pretty terrible, but you know you kindly get used to it. Voltage set here. we've actually got to push the knob is possible like this.

Well, actually, let's uh, so we can go up like that. We've got ourselves a fight up there. We go. boom and how do we get out of there there.

go and we can actually go down like this. And we can set our output current limit of course and you can't let is just your LED brightness and there's some presets if you want to do it that way, but it certainly is not the most user-friendly thing. anyway. we'll switch that on there we go: 5 volts, 0.99 3 amps, point 9, 9, 9 on electronic BK precision electronic load here, which is 0.05 percent class so you know there's a little bit of error there on the measured current so, but it's not too far off at all so that's not too shabby.

Hmm. I like that. by the way, the output voltage is going to drop because of the leads there I Haven't got any remote sensing or anything like that, so don't worry about that, but that is that is very nice. Now this DPS 3 double O 3 module is a little bit more expensive than this one here which we had before but not much.

This was like 18 dollars on ebay delivered. This one's like 23 24 dollars delivered so it like there's nothing much you know I Kind of like this one a bit better but of course this doesn't operate. If you want to use it, say for a 5 volt plug pack or something like that, this one won't be suitable. You've got to get the other module which goes down to our 5 volts, this is only 6 volt minimum input voltage.

and anyway this module only claims 0.5% plus one digit which is hay more than enough for a just a cheap pinch supply like this. No worries at all. And there we are. We are able to draw up to the maximum 3 amps and I'm drawing 3.

Answer my constant current load there: Three Point Zero Zero Oh, two Point Nine Nine nine and we get into point Nine Eight Eight readings. a little bit out, but hey, that's doing that. Um, so we'll actually get the thermal camera on the back of that and have a look. Well, I'll tell you what.

I don't even need the thermal camera. We're delivering our 15 Watts here and I can stick my fingers on the back of that heat sink there and no problems whatsoever. It's barely even warm, so this sucker at that potato, a 12 volt input voltage with 15 watts output like that is pretty done. Efficient.

Nice. Okay. I've had this running for a while with ten point nine one volts output at three amps and it's starting to get fairly warm. But I could still keep my fingers on that.

so it's not up to 50. it's probably at, you know, the high 30s, maybe the low 40s there. but this is kind of the level at the sort of you know, the 33 what level Especially, you put this in a steel case you'd be looking at, maybe having a little fan in there just to actually add some vent holes to. You know, get some airflow over the heatsink fins in there and things like that, but you know that's a fair amount.

You know you when you're pairing projects, you're generally not going to do that from like, just a simple plug pack type input like this. But anyway, the purpose of today's video is just to show you these little modules. not to actually I characterize them and do everything else because I'd need a different plug pack if I wanted to fully characterize this module which is 96 watts. Wow Anyway, I Do like the secondary output our display up here.

it still shows the output when you're in the set menu. That's kind of cool. The Nod does absolutely nothing when you're in the when you're in the main display mode like this, which is good. can't excellently bump the output and I Also like that it shows the voltage input here coming from the plug pack.

That's really handy. I Probably prefer this module over the other one we originally saw with the multi-line display. It's just like it's like bigger, color-coded It's just kind of nicer. I'd go for this one anyway if we have a closer look inside the DPS Three double a three here.

bottom is a display board in here. The top is obviously your main switching convert. If you main switching trainees under here, we've got ourselves the big current shunt there. That's kind of neat.

Which device does it use? mm-hmm I'd like to reverse engineer the circuit on these and the main converter chip in here is an Excel 705 never heard of it comes from a company called Excel semi. I'll link in the datasheet down below but that's only I rated for 1.2 5 volt minimum output is. most converters are not so learns a bit you doing in there. Um yeah yeah.

Frosty the Snowman So yeah. I'm not sure how they're getting the one point the the zero volt output from that, but there you go. We've got a few miscellaneous other devices down there. like I said I'd like to reverse engineer if anyone knows.

we can get a schematic for any of these and I'd love to know. Please leave it in the comments. Otherwise yeah, requires a little bit of re and if you think these modules are a little bit wimpy and you want something better, well, you can try one of these bad boys. Ah, here we go.

Where are we? Digital Buck Boost Power Supply: 6 240 volts input 32 volts output 0 to 5 amps hundred and 60 watts maximum allowable input current 10 hours Lullaby Make sure higher than 18 volts Liar. Okay, so they've got some. Once again, 0.5% one milliamp output Quite nice. so they've got that.

but these are separate. So you actually get the module separate on here and this one is. Oh, there you go. It's the same sort of interface, but except it's on a cable which then you hook up.

you get the cable with it by the way. and this one's about for just over 40 U.s. bucks. And this one's got the little mini fan on the back, so that's quite nice.

You can actually mount that easily in a little case like I've got here. You could duck, yeah, fit in there and fit in there. A treat. look at that.

So I could fit that in the little case I've got, so that looks really quite neat and jazzy, doesn't it? There's our output current shunt. I've got a couple of big trends in there. I'm not sure what those ones who are those caps from do we want to know and you wait nicely. The last secondary board there, you've got your micro powering the whole damn thing, but that is really quite nice.

and it looks like there's four terminals on the inputs, four terminals on the output, and a little mini fan. It's probably as loud as buggery, but you know what not. But hey, just these modules. The fact that you can get these in any flavour is just fantastic.

I've got another one. Hang on. We want a bad boy. zero out of 32 volt output, zero to 12 and DPS Thirty twelve.

I might have to do a separate video actually building one. Once again. you get that and you get the board in there. look Joule current shunts down in there for that one.

Forgive me for taking it out, but like like little pissant fan on there for like, give me a break. 32 volt 12 amp output capability with that kind of heat sinking. That's a joke, right? But anyway, for the price, you're not gonna complain. These things are just cute.

Anyway, this one's rather interesting. Got ourselves an ST micro. They're running the show as our converter is it TI Jyoti or Five Nine for classic. Can have a look around some of the other stuff if you're the least bit interested.

There you go, but a couple of odd they were a couple of MOSFETs Were they? Hmm. Anyway, this looks like a rather neat module. Yeah, here's the brand on that. I'm not entirely sure one hung Are they Are they roam power transistors? Is that the are? Oh there you go.

Two of them, are you doing a parallel job'? There are they? Anyway, that would make a very interesting project. maybe like you can always take those transistors off, mount them externally on a much larger heatsink and actually turn that into a really neat project cuz you know, like 12 volt like I Don't really believe the specs on these things but yet to be proven, but you know to have a 0 to 32 volt 12 amp supply basically all done for you with the user interface and all the power supply control stuff that you know for the price is just absolutely amazing. Just waking into a case and have a suitable power sway like a PC modified PC power supply hooked up to it for example. let it do the business so that might make an interesting project.

I might give you know work on putting it, you know you put it in a nice case and everything. do it properly and everything else. but yeah. I Just like the concept of these modules that you can get them in any shape or form for you know, hardly any cost and they might be a bit buggy or whatnot in the performance probably isn't going to be great and they're probably not going to live up to their specs or whatever, but the fact that they're so cheap and can make you know a like a half decent power supply.

hmm. Anyway let's say like a scope up to this and see what's what. Alright, let's power this thing up. I've got a 10 volt I said a 10 volt output with a 3 amp load on our constant current load here.

and let's switch the digital output on and we'll capture that and that is as clean as a whistle. What's that? 500 milliseconds per division, 100 millivolt switch on? That's just fine and dandy. There's no overshoot whatsoever, has over current and over voltage Our setpoint protection as well. that's just a soft and software thing.

They're are not doing that in hardware, but that's good. You can. You know if you don't want to damage something, set it to our you know, 5 point 5 volts or something. You got a critical board 5 point 5 volts and it shouldn't go over.

but it said software things so I wouldn't rely on that. Not as good as a hardware one In something you don't see that often is a output power protection as well. Um, I don't know some people might need that. Okay, I've got the constant current set to 2 amps here, but I've got a 3 amp load.

so let's just, uh, switch that on and see what happens. It should get 2 amps there. you go. We've only got point 1 2 volts out, but we are getting in our constant current.

2 amps is limited that all right. So that's gonna be our bloody load here. Let's just set it and we'll just short the output with the leads. That's better.

These loads can be annoying sometimes. Alright, so just sit 10 volts, 2 ampere, put more, just short this puppy and see what we get. Hey, that's a nice, nice clean response. Look at that, no worries, and let's see what response we get if we take it out of short and it goes back to 10 volts.

That's pretty clean - don't mind that. And by the way, these are all our step-down converters. They're not our buck and boost, so it's not like in feed in five volts in and then get the other outputs. That's why this one only goes to a maximum of eleven point two six volts because we're only feeding in twelve volts.

So if you want higher than that, then you have to go up. This is rated from zero to forty volts input. so if you want the 32 volts out, you've got to have at least 32 volts plus the dropout voltage in because they're only a buck type device Anyway, in constant current mode: I've had the output on that Whoop! I've had the output shorted at 2 amps on this thing for quite some time now and that's not even warm. Not at all so neat.

And for those who want to see the switch in noise 65 kilohertz there this is at 3 amps at 10 volt output and well, it is what it is, you know, and like just for a ruffer's guts, our power supply. That's just fine. You can probably add some extra filter in on the output if you're really wanted to, but you know, man, that'll do for a lot of projects. Let's just repeat that power on test with a 22 I'm load here so we don't have the active electronic load in place and we'll switch it on and clean as a whistle.

We'll just set the negative trigger there and we'll switch it off and Bingo! That's a nice clean switch off in 50 milliseconds or so with that load. Of course it'll take longer if you totally disconnect the load of course and I was a bit warm. E and then single shot switch it off. Of course the output capacitance will take forever, so that takes about four hundred and something milli add self.

We set it to 300 milliamp current limit and I've got 10 volt output and we and I'll just give that a little whoop. switch on. There we go. That's actually the response of the constant current mode so it it under shoots there in terms of the voltage.

but that's okay. no harm done there, but it recovers, you know, 50 milliseconds or so, so that's quite nice. And then if I set it to the positive edge and lift her up, there we go. That's a response going from constant current mode with the voltage limit.

They're up to the ten volts and there's very little overshoot there that's very nice. No problems. of course we haven't checked this over. It's full operational range, but that's a pretty good indication that so I going to work like that over the full range though.

So there you have it. these these nifty little modules from company unknown available from all and sundry on Aliexpress and eBay and a would bang good wherever you want to get these things from. And they cost practically nothing like 17 Doe Lyke? No, sorry. This module is about twenty three, twenty-four dollars delivered or whatever, and you just have to whack in a plug pack of a suitably high voltage.

Depends on what output voltage you're looking out for this thing, and performance is probably going to be half reasonable. The UI is half reasonable and jeez, it's worth. like probably building one of these. They found a real nice niche with these modules.

I think I Don't think there's anyone else actually doing these, whether or not someone company making them or others have ripped them off. and there's clones of whatever I Have no idea. But yeah, they've got a pretty nice little niche with these modules. I Rather like them, the more experimentation required I'd like to fully characterize them, but that's a lot of effort for fully characterizing over the input voltage range.

I Like various input voltage ranges for all the different output voltages, through all the different output currents, and yet all the characteristic curves and makes my head spin just thinking about it. And but they're probably gonna give reasonable performance how it's worth for the money, it absolutely cannot be beat. Just build it using our junk bin you know, parts, a couple of binding posts in an old plug pack you got lying around. we know, winner chicken dinner anyway.

I Hope you like that If you did, please give a big thumbs up. And if you want me to do more videos on these modules ever you know taking one of these big beefy ones and actually you know, making up a big beefy like you know, 10 or 12 amp power supply or something like that. Let know in the comments down below and as always, discuss over in the Eevblog for him. Catch you next time you.

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