Hi welcome to another video in the USB Power Supply Design series and uh I'm just going to do some measurements on um, this little uh 2 W uh DC to DC converter. You've uh, seen these before. It's one of these single inline uh package types 5 Vols in over here 5 volts uh out you can get ones with extra pins that have like a split uh Supply as well, but I'm using five 5 Vols in 5 Vols out and this one's a 1000 Vols isol. Between input and output, you can get higher and uh, we'll go into some uh detail on why, hopefully why that might be important.

Now this is a Sang May brand Sangi however you want to pronounce it um brand and uh I'd love to pull one apart but they're fully uh potted. You can see the potting uh compound in there that is effectively is just a plastic uh you know, uh outer uh box a plastic IC potting box which they silk screened and then they put the circuitry on there on a little uh circuit board of course and then they Gunk the whole thing up. but I might try and maybe open one but um yeah it's it's just going to be completely gunked I'd have to use some chemicals to deunk the thing to show you what's inside Anyway, they're a diamond doesn't um uh. industry standard uh Footprints of this is one of one of the industry standard Footprints available in the single in line package one, but there's many types available under many different brands.

Sang is just one of you know, dozens and dozens, countless, uh, DC to DC converter manufacturers. This is a little 2 wat, uh, one and two wats is specified at the output and we'll look at the efficiency I'm going to compare it with the data sheet, check minimum uh, loads and efficiency and stuff like that might be a long video, so hang in there. and if we have a look at the data sheet for it here, there's not a huge amount of info. There are some specs.

there's some uh, typical output, uh, characteristics, but there's no Um info in terms of minimum output, capacitance, or anything like that. So um, anyway, we're going to, uh, give this a try and this is a 1 kilovolt one. As you can see, it's uh, 2 wats, um, output uh Power capability and uh, it's it says it's an unregulated um, uh output so it's not. You know it doesn't have like a linear regulator.

uh output. It's a 1000 volts um, isolation. It It says 1,000 3000 but I'm pretty sure this is the one uh, th000 volt isolation version I Think there's another version you can get which is 3,000 volts isolation and uh, up to 80% efficiency. That's fairly typical of these little uh modules.

Um, unfortunately, you know you're not going to get one or you. You know you're going to pay a lot more if you want one that's optimized for a specific load. um, and you know, gets over 90% but 80% is pretty typical. We'll uh, test that working temperature range -40 to + 85 um Mtbf which is the meantime.

between Uh failures is uh, 350,000 hours and if you do the math on that, that's like 145,000 days or uh, 40 years or thereabout. So H go figure. It's got 15 % load regulation here for a Uh I presume that's a load range of Uh 10% to 100% and uh, we' got some Ripple and noise up figures here: less than 75 molts. These things aren't particularly quiet.

if you want to make them quiet, you got to put like a Feride uh, Ferite bead on the Uh output um as as well as a Um linear Uh voltage regulator too if you really want to, um, bang that noise down. So um, we it, uh, we've got down here here. We got the 5V version here. it's 4.5 minimum uh, volts input.

We'll uh, check that um, because if you're PA in one of these things from USB you can actually get less than 4.5 uh, due to the drop of the Uh cable and stuff like that. so uh, maximum, uh USB current 500 milliamps and uh, where it says uh, 40 milliamps minimum load on this sucker So I'm very curious to try that out and whether or not it uh, works with lot no load I'm pretty darn sure it does. Um, and a maximum output of course of 400 milliamps at 5 Vols there's your 2 watt. So uh, actually, this is perfectly rated.

for a USB application. you might think oh, you need 500 milliamps output Aha, no, it's not going to do you any good because remember that 80% efficiency figure up there. So let's assume that you can actually get 80% efficiency from this thing. Your Us USB can only in theory uh, provide a maximum of 500 milliamps.

So um, 500 milliamps into the DC Todc converter with 80% efficiency means you're only going to get out 40400 milliamps. So it's absolutely perfect. So you actually need an 80% 2 W DC Todc converter for a nominal 2 1/2 watt USB port. and it doesn't tell you anything about uh, you know, short circuit protection, under voltage, uh, lockout, and uh, stuff like that.

So um, these are the sorts of things that we'll have to check. There are two more pages to the data sheets, but it's just uh, pinouts and uh, physical descriptions. And here's the setup. Nothing, uh, fancy.

Just got it on a breadboard here at the moment I've got no output capacitance I've got 2 meters here. this is my input voltage and this is my input current coming from my bench power supply. I've got my uh, trusty BK precision 8500 electronic load so this, um I don't need extra multimeters. You know how I've often use four multimeters to do this DC to DC converter stuff.

Well, this one measures the voltage, current, and allows us to do the power and uh, stuff like that as well. And it's um, just as precise as a fluke 87 basically. so uh, that's going to work a treat for measuring the output voltage and current. And I got a couple of probes that allow us to probe the output on the scope up here.

one set to Uh DC and one set to AC. So let's go all right now. what we're looking at here: Um I've got Channel One, which is the yellow waveform at the top that's set to DC so we can see our DC level at 1 Vols per division there. So we're getting our 1, 2, 3, 4, 5.

It's around about 6 volts there. it's actually 5.87 according to the BK precision there. and Channel 2 the green waveform here I've set up uh, exactly the the same measuring the same point, but it's AC coupled so it allows us to see the DC level the same time as AC. Would have been nice if the scope could.

uh, do that on one probe, but it can't So we've got the um uh AC coupled waveform here at 200 MTS per Division and you can see and I'm measuring the frequency of that. you can see the automated cursors there jumping around. Um, we've got Uh 50 very large amount of 50 htz and by the way, this is with no load. So um, uh, the data sheet sort of implies that it needs like a 40 milliamp uh load minimum on the output.

So this has no load and no output capacitance except for the input of the Uh BK precision. But that 50 HZ Wow, that's uh I Really did not expect that at all Now I Have a sneaking suspicion that the electronic load is causing that, so let's disconnect. Hey, yep, there we go. We just get our switching noise.

So just the fact of having that electronic load on there means we get that 50 HZ hum. Look at that. and by the way, you can probably see this uh. waveform.

Jump Around Occasionally, there we go the Uh. That implies that you can see the switching noise on the waveform there. and uh, that means that the trigger is sometimes switching. uh, sometimes triggering on that noise on there.

So that's why you're getting the waveform jumping around like that. So if you've ever got and like a waveform that's not a noisy waveform like that and you can't trigger off, well, we go into the trigger the the mode coupling menu and there's various options: Noise, noise reject if we I need it to jump around for me consistently. But anyway, if if you hit noise reject, that will reject uh, the noise in the triggering system of the scope and we should never see that jump around again. Hopefully, And if you really want to, you can switch in HF rejection as well.

high frequency rejection too. but uh, that should do the business. Just as a quick little test here: I'm going to leave my ground probes uh, floating? I'm not going to connect those and I'm going to um, use a poor man's different turn my scope into a poor man's differential uh probe here by connecting by using two channels and one before we had the ground hooked up to the negative uh output and we were probing uh, the same channel twice. but now I'm using two different channels to Via the high impedance of the probe.

of course that's important. Um to probe differentially the output, ground and 5 Vols and I can do that up on the scope here by by uh, going into the math uh menu and subtracting channel one from Channel 2 and you can do this on on Old analog Scopes as well, but also works on digital. so I end up with the white math wave form which is channel 2 minus Channel 1 which is effectively a differential probe. It's a poor man's differential probe because the uh uh, common mode rejection ratio is pretty terrible with these probes.

it has to do with the matching of the put uh impedances and stuff and it's You know, it's uh, it's but it works as a poor man's differential probe and we still get that 50 htz there. So there you go, and that's uh, showing that it's um, it wasn't the ground connections on our probe causing that. And the other thing when you're probing um DC todc converters like this and you know I've got a 500 MHz scope here. You really don't want the full system bandwidth this thing.

so you really want you know you can see the huge amount of switching noise in there and so you know if you really want to clean that up because of the massive bandwidth of the scope. Um often. um, you want to put on the 20 MHz limit and that comes into its own when you do the measurements because you can see the Uh output Ripple and noise is specified as less than 75 MTS Peak to Peak over a 20 mahz bandwidth range. So turning on the full bandwidth of your 500 MHz scope or your 100 mahz scope and then complaining that the ripples are larger than claimed? Well, you're making a mistake.

So um, you know, really, you want to, uh, turn on that bandwidth limit which in this case is 20 MHz And the reason it's 20 MHz is because, uh, to match the old traditional Um analog Scopes which for a long time your entry level analog scope was 20 MHz Now I suspect that if we wind up our load here, um, our 50 Htz is going to completely vanish. and yep, as we as we go up the 50 HZ Let's take it to say that 40 milliamps, you know, Minimum, we're still. You know it's still got some crap there. But uh, let's see if a pure resistive uh load makes any difference.

And yep, that's with a pure resistive load there. And of course, and we're getting no 50 Htz at all. And uh, that's with the um, that's with the resistive load. Tiny little resistive load down in there and disconnected from our electronic load.

Now here's an absolute classic example of Burden voltage on a on the current range of a multimeter at work. Here, we've got 5 volts input voltage. Uh, that's measured by the way. right at these two uh uh, alligator clips there are right at the input terminals to the voltage regulator.

So um, uh, obviously the voltage at our Uh power supply up here will be, uh, higher. because of the voltage drop. There'll be some slight voltage drop in the cable. But let's take a look at this.

We're at 40 milliamps at the moment and I'm going to turn up this output load and watch this input voltage here drop. Let's go up to let's go up to a couple hundred milliamps, right? So let's go say 200 milliamps output current. Okay, look at where we're at with this input voltage is 42 volts. That's right on the minimum input of what the data sheet claims for this DC to DC converter and the output voltage of the DC to DC converter is dropped as well cuz it's not fully.

it's not a fully regulated Uh converter. So um, and we got 260 um. milliamps input current and you might think aha, the voltage is being dropped by the leads coming from here. but no, aha, watch this ready I will change.

It's the Uh burden voltage of the milliamp. Uh Jack here I turn over to amps Bingo We got our same current but look, the voltage has jumped right back up to 5. Vols There is no drop in these leads or very little um, it was all inside the Burden voltage. That multimeter.

What a bastard trap for young players. There's two ways around it either to use my microcurrent. If you really want to do this, then you have to be if you really want. But you see with the 10 Amp over here.

Okay, our our resolution has dropped. So if you want to keep that resolution okay, it's dropped to four and a half volts. There it is. You have to compensate for the drop the burden voltage in the drop of voltage in this meter by turning up your input voltage back to 5 volts.

So as you increase this current here, you've got to increase your you've got to adjust your power supply at the same time to track and compensate for the drop in there. and you'll notice if I switch it over to Amps. Now there's practically no Verden voltage on the amp range. We're at 5 1/2 volts burden voltage trap for young players.

beware, but there are ways around it now. As for this 50 HZ issue with this electronic load, it is rather puzzling if I switch the if, if I disconnect it. of course it vanishes, right? And if I switch it off via there, it vanishes and you know there's hardly any load. It's like, you know, 1 milliamp low there? If anything, it's practically turned down to zero, but it really starts injecting that massive amounts.

We're talking 200 molts per division there. So we're talking half a volt of 50 Hertz hum into our measurement system here now. Unfortunately, I'm not able to get rid of that, so that's just inherent in our test setup. With uh, this electronic uh load.

It's um, it's basically picking up uh 50 HZ from from inside the supply and then it's um, couping that into back into the DC Todc converter at low currents because of course, once you go up in current, it just it. It just vanishes even if you go up in a couple of milliamps there it and then it eventually just vanishes into the usual background noise. So that's how DC Todc converter causing the issue here because it's only when measuring the output of the DC to DC converter. and even if I uh Bridge the uh isolation in there, it makes absolutely no difference at all.

So this is short in the primary and secondary of our DC to DC converter and the high frequency Uh noise has dropped. but the 50 HZ remains and at the exact same scenario. So that's the that's a minimum load thing on the DC to DC converter causing that issue combined without our electronic load. because if I disconnect the load and put just a resistive Uh load on the output, of course it vanishes.

So we're just going to have to put up with that for the time being, but it won't affect our measurements now. There's something I hinted at there while Uh I was shorting out the primary and secondary, the noise uh, the switching noise vanished and the reason we're getting switching noise. It's Um Universal with these Uh DC to DC converters and what's causing it is the capacitance between the primary and the secondary of the Transformer inside this DC to DC converter. Because it's an isolated Uh Transformer and the capacitance of this thing will basically uh determine how much switching noise uh is going to be coupled into your systems now.

I Said that this is a 1 Kolt converter. you'll find that the higher voltage DC Todc converters here I if we use the 3 kilovolt version or you can get five and 7 Kilt versions of these type of switching Regulators the higher that isolation voltage, the lower um your switching noise is uh going to be caused by your primary and secondary capacitance? Why? Because the greater isolation voltage means, uh, greater physical separation between the primary and secondary and therefore lower capacitance. So how do we? Um, So A If you want to lower it, you can simply use a higher voltage rated DC to DC converter. But then they're bigger, more expensive.

So the way to fix it is to use a high voltage suppression cap. and you can buy caps for just this purpose. And here we go. We've got a 3 Kolt, uh 102 there.

Which means it's 1 Nanofarad. Now if you have a look at the Uh switching noise here, it's really high frequency stuff. And really, if you got your bandwidth limit of your scope turned on here, then you're uh, pretty much fooling yourself in terms of how of the Uh level of the actual switching noise. So if you switch that off, you can see that.

The massive high frequency stuff. You know we're talking 70 odd megahertz, 70 plus megahertz here. So that gives us a value of what you know. There's roughly you know, three divisions there or thereabout.

So we're talking 600 MTS Peak to Peak. But the issue is, look down here. I mean we've got these horrible antenna ground leads all over the place. Horrible.

Look at the inductance of these things. So what we need to do is uh, this sucker properly And by that I mean you want to get rid of this antenna ground. Lead here. And this tip and get what should have come in the packet with your probe.

one of these little low inductance probing points. So look at the tiny amount of inductance there compared to this huge lead here. plus the tip I mean ah, no contest. and I know, Um, everyone will mention it.

Yeah, this is crap, right? I'm trying to do this on a breadboard. it's you know it's going to be horrible to begin with, but we'll be able to see the difference. what we get 600 MTS odd last time. so let's try.

And the good thing about this is that it is thin enough to actually stick down into. Sorry, you can't see that but I'm pushing that down into the the pro Point down into the breadboard there and Bingo! Look what? We have same volts per Division 200 Ms per division, but much much smaller amplitude and that's what's really there. So we're only talking. Now you know, 200 M volts or so.

high frequency noise on there and of course this thing's going to jump up and down like a jack rabbit. You know I can fart halfway across the room and this thing's going to uh, going to change around. but there you go. that is at least um, the the proper way to attempt to probe such a thing.

But I think I've uh, digressed a fair bit I don't uh, really? um I'm not here to measure the Uh switching. uh Transit and trying to fix that and do it on a breadboard and all that sort of crap I don't really care I Umum, more care about the uh efficiency of this thing. and uh, and its load performance and stuff like that, right? So one of the first things I've noticed is that it, um, essentially doesn't need any output capacitor on this thing. I mean I've got no output, uh, capacitance? um, at all and we're driving.

You know? let's let's take up the load to Let's really bump up the load here. Quite significant output. Let's go to its maximum actually. Tada I Love this electronic load.

It's great and we're still getting a 4.93 that's with no output capacitance at all. input voltage of 4.9 volts. There it is. um, I've just got a little uh, bypass cap on the input there, but uh, no output capacitance at all.

And if I add A47. So half a microfarad and uh, you know, really, there's uh, there's nothing there. It doesn't affect the uh Ripple or noise performance of this thing at all. It makes absolutely no difference I'm not showing the scope scope screen there, but uh, trust me and uh, makes absolutely no difference to the output so there's no stability issues.

Let's try 47 microfarad. Electro Once again, makes no difference to the switching noise of the output. Ripple it's still all, uh, nice and stable over um, basically any capacitive load on the output. excellent.

and uh, of course it's not very well regulated in terms of input to Output regulation and it tells you that. So let's wind up your input and you see the see. the output. Basically Al uh corresponds to the input.

That's basically what it's doing. Um, almost precisely actually. and it's supposed to work down to 4 and 1/2 volts. So let's let's see where it kills itself at its maximum output current of 400 milliamp.

So we're down to 4.5 You could easily get that on the USB if you uh, had a big voltage drop and it's working. it's still working down to still working down to 4 Vols input and we're getting 3.8 So it seems to it's diverging a bit more there. But really, it's still working. A treat at full load.

No problems at all. Wow, Um, you'll see as I adjust the actually I'll probably put it up. here. you can see the uh, you'll be able to see the frequency change or turn that input voltage back up.

Actually, the scope's rather, uh, annoying here in that, um, it's in automated frequency measurement mode. It's tracking that individual. You know it's tracking that high frequency stuff in there because it's got such a deep memory that when it samples it, you know it's got all that high frequency content in memory. And even when you go right, oh, there we go.

it's just jumped out. Now we can see the switching frequency of the regulator. So To avoid that little trick you can do is just offset your waveform a bit. and because it's right smacking the center.

now if we Center it just offset it a bit from that. Center And bingo, it'll find the Uh Peaks elsewhere in the waveform and now it will track that. So we're looking at 160 odd kerz there. So for the switching frequency, now, let's drop.

Let's drop the Uh input voltage here. We should be able to get all the displays on the screen there. Yep, Okay, that's it. Uh, drop our input.

That's at 5 Vols input. It's got 160 khz and as it goes down, we're going to have to switch that down. 4 volts sorry. uh.

decreasing. Oops, it's now. it's it's jumping all over the shop there. It doesn't like that and uh, it's decreasing.

but interestingly, it really does continue to work at. Look, we're talking two. you know, two volts input and it's still going at full output current. This is really a nice little DC Todc converter works much further over the range than way there we go.

And to start back up, we've got to. We've got to hit a minimum threshold voltage. Our output voltage has died, so there we go. It really did not like that I Had to cycle the Uh, had to cycle the load on the output here, and uh, but it can certainly survive under voltage dropouts way below that 4.5v data sheet rating.

so that's brilliant. I Like that and uh, and we're still. It looks like it's getting better than 80% efficiency here because we're not at 500 milliamps for our Uh input current. So let's do that.

Let's get a graph of the efficiency of this thing. um, with output current. So what I want to do now is get a plot of uh, the efficiency versus different output power levels. So what I'm going to do is use constant power mode here, which is you can see the little CW Uh symbol on there and basically that will, uh, keep a value of you Well, I'm going to start out you know, in various increments all the way up um from basically 0 to 2 Watt and I'll keep the input voltage the same at 5 Vols all the way through and we'll get you know, a dozen or two dozen uh data points and we'll be able to plot the efficiency of this thing for different load output.

Powers Uhoh we have an intruder intruder alert intruder alert up. Hey Look, you want to play. Wow. Look, we got oscilloscope, electronic load multimeters, a breadboard.

Wow. Oh yeah, they're pots. You want to. You want to play with the pots? You want to tweak the pots.

You got to hold your tongue at the right angle. Yes, Oh good boy. Wow, that's fun. Isn't it all right? Yeah, Isn't that cool pliers You want some pliers? You want some pliers? No, no, you don't want pliers.

No, you want a screwdriver. Instead, you want a screwdriver. Daddy will give you a screwdriver. How's that? Oh yay! Oops, you shorted it out dude.

And I've had this thing going at a maximum 2 Watts for over an hour now and uh, I'm getting about 45 on the uh top of the top of the unit there. so it's uh, staying relatively cool really? Um, you know that's only 25 C above ambient. So here's our result in Dave CAD 0.1 watt increments all the way up to it's rated value of two Watts here and you put those in the PC and here they are P out, V out, V in, I in P in and calculate the efficiency as well and Taada. And here's the final plot.

If you plot the efficiency on the Y AIS here versus Power output on the x-axis from uh zero load to 2 Watts load, you can see the efficiency and it's a classic sort of graphing. It drops right down of course at the lower end, but the majority of the range, you know, a good half of the range is 80% or more. Um, from a watt to two watts. and then even from you know, a half Watt upwards, it's still.

you know, 75% there. So or just just over 70 sorry at um, uh, half a watt so it's still pretty darn good. 70 to 80% And of course, at very low loads, you expect it to be very inefficient. but that worked.

A treat if we just have a quick look at some of the output. uh, noise here. Pretty horrible. Uh stuff.

I can, uh, knock that on the head there? That's 50 MTS per Division I Can knock some of that on the head there by putting a Um RFI suppression cap between primary and secondary and that? That's one Nanofarad knocks it on the head a little bit and the data sheet claims less than 75 molts Peak to- Peak Ripple and noise. Um, at? well, uh, presumably at uh, full rated Uh output current. So we've got the full output current here: 400 milliamps, uh, 2 watts and um, we're basically getting 50 Ms per division. There There you go.

it's uh, certainly in the ballpark and that's with, you know, dodgy breadboard, dodgy, um, grounding and probing and all that sort of stuff. So yeah, it's a certainly meeting. Uh, all its specs. So far, what we're going to do now is test its.

uh. switch on performance at uh, full load to see uh, if it overshoots. So we got full 2 wats uh output constant uh Power load and uh, let's switch it on. That's well, switch it off first.

input is Switched Off off and I'm about to switch the input on and hey, there we go. Look at that, that's 1 V per division. So if we take a look at that, we're looking at 1, 2, 3, 4, 5, six. We' got some overshoot.

There goes to just over 6 volts. Got some uh, ripply stuff happening there. Some of that 50 HZ stuff is kicking in, but then it jumps back down. After what? 50 milliseconds? Yeah, 50 odd milliseconds jumps back down and then regulates.

Basically. Not that this thing is actually regulating, it's just following the input. uh, voltage. basically.

So if you're pairing real critical stuff with these unregulated in quote marks unregulated, uh DC Todc converters, then uh yeah. you'd have to watch out for uh, that sort of overshoot. And let's see if it uh, starts up at uh, the full 2 wats at lower voltages. Let's see if it starts up at 4 volts.

So let's uh, switch the input voltage off, switch it on. Bang. No problems at all. 4 volts.

Once again, overshoot that overshoot to five. No worries. So it starts up well below it's rated uh, input voltage into full load because it's claiming uh, 4 and a half. You know, minimum 4 and 1/2 input volts.

Um, but let's let's give that another go at 3 volts this time. 3 Vols Input bang? No, didn't like that it uh switched, switched back off, didn't didn't like that at all. Bang? No, it really. No, it doesn't.

uh, doesn't like that. Let's 3 and 1/2 let's say reset and bang. There We go 3 and 1/2 volts. Not a problem, sorry, uh 3 3 Vols not a problem and our output current of course.

Um, we're still outputting 2 Wats constant power load and we're getting 7 amps out at Uh 2.87 So this thing, uh, certainly does, um exceed its data sheet specs and I'm getting a lot of confidence with this thing right now. Let's stress this puppy. Let's uh, go over the two watts and uh, see if we can hurt it. Well, that's a bit bit touchy this knob.

sometimes it increases 2 1/2 watts and uh, and we're still kicking in there with our uh oh set of course. um, we're still kicking in there. We got uh 4.85 volts out and uh, half an a. over half an amp there.

Not a problem. so let's 4.7 volts. There you go. 3 Watts get the wet wet finger on that.

Yeah, it's getting pretty hot now. I'm going to, uh, get the old thermometer out and see what temperature it's at. And while we're over 50 on the uh, left hand or because I think it's back to front, it's the right hand side of the device. Looking from the silk screen, it is hotter on that side than it is on the other.

It's uh, bit cooler on that side, but this side here is certainly. uh, certainly getting quite warm so, but it's still holding in there. Um, it's it's delivering. It's delivering 3 wats and uh, it's only a 2 wat rated device so it's doing pretty well.

I wonder if, uh, wonder how long it will actually uh, go like that and you can see our output Ripple is uh, drastically increased. but I just hit the switch and uh, restarted that thing even at 3 what load it restarted? No drama. So oops, I just killed it with that cap. obviously because I pluged the cap in live.

Let's boot it up. there we go. So our Ripple is AR I It's still, uh, quite significant. It's a little bit higher without the cap.

now. 5 minutes later, it's still holding in there at at 3. Watts Not a drama. So I mean it's getting.

it's getting BL hot I can't touch that. but uh still. I'm pretty impressed. We're certainly creeping up towards 60 here.

I mean this is not the best probing solution I'm just holding my thermocouple on the top on the plastic top of the case. there. it's going to be hotter inside. Of course, the circuitry the uh uh, thermal resistance of the case is going to be fairly high, but uh, there you go.

Yeah, we're crack 60 and of course you certainly wouldn't over. you know, design your product to overload this thing so you would work within the you know, the two wat stated specification of course. but you know it can deliver a uh a You know, a temporary increase in output power at the very least. and I think it's time to get a bit brutal I'm going to short the output.

Here we go see if we can survive a short circuit doesn't say in the data sheet if it's uh, short circuit proof Wham There we go with the shorted output. 5 volts uh input. We're getting uh, 370 milliamps on the input there and uh, I'm just going to leave it shorted cuz I'm a cruel bastard I'm going to leave that shorted and uh, see what happens? Well, it's still going and of course, with a shorted output 5 Vols time. Uh4 is that 2 wat.

So it's delivering the full two watts into no load. So where's it all going? Well, it's all going into there so this poor little package now has to dissipate two. Watts instead of um, delivering 2 watts to the load and being 80% efficient, only going to normally dissipate 20% of that 2 Watts Check it out, We getting up to 100? almost 100? Celsius on this sucker. In fact, I'm sure it is, and of course it'll be hotter inside, but it's been like over 10 minutes, maybe 15 minutes.

and uh, with this sucker shorted out and it is still still hanging in there, cannot kill it. I'm sure it will eventually, uh die, but geez, it can certainly handle a uh, a 10-minute uh, complete short on the output. Great stuff. Well there you have it.

I think I'll uh put, put it out of its misery there, remove the short bang and it should, uh, drop back to normal. but uh I hope you like that that was H just some quick little uh tests on a nice little 2 wat DC to DC converter. It's a robust little sucker. It seems to exceed, um, all of its uh specs and works uh, quite well.

It isn't unregulated, uh, type, of course, so it's output uh voltage effectively follows the input voltage. but um, I you know that's exactly what I uh want here I don't need a regulated a fully regulated uh converter because I've got a F- regulator afterwards so it doesn't matter a rat's ass really. But uh, it's a it's a neat little whoa whoa whoa hot hot hot hot hot hot hot hot Oh man woo. Hot Potato Hot Potato um Anyway, there you go.

That's a little two watt converter. Hope you liked it. and uh, as always, if you wanted to discuss it, jump on over to the Eev blog forum and if you like the video, please give it a big thumbs up. Catch you next time! M toasty.