Hi, Its teardown time. We've got another linear bench power supply. It's the new sibling SPD 3303 X-series our programmable power supply as all new sibling gear is, it's all the new X-series They're designed to work together and I don't have a similar look and feel or something like that. But anyway, this is a five hundred and thirty nine US dollar street price, triple output, 220 watts or there abouts power supply as that the model number gives it away.

We're looking at 30 volts are three amps per channel slightly over that actually and a fixed voltage output here. So yes, it's a real big thump and linear power supply. None of this switch mode rubbish. It's got Universal voltage input on the well, switchable voltage input on the back here, so it doesn't matter what region you're in, you can switch it to your voltage.

It's our Ethernet enabled of course, all programmable functionality and it's a precision power supply. We're looking at one milli volt, one milliamp resolution on the thing, which is that order of magnitude ten times better than the Riga Rd Dp8 3/2 power supply because you have to buy with the RAI goal. you've got to buy the software option to get this the resolution that this one has so we'll worry about how it works and all that sort of jazz later. What we want to see now is what's inside.

You know what we say under here on the Eevblog Don't turn it on, Take it apart now. It looks and feels fairly decent quality. It's got a decent carry handle on the top and I've got no major issues with it except the binding. Posehn could have been a bit higher quality I don't know, they just feel a little bit sheepish I sort of maybe would have liked a bit better and the holes on them for the wires are pretty darn small.

look at that. I would have preferred big beefier hole so that you can get you know decent cable into these things because this thing you know 3 amps and you can parallel the thing for even higher current. So yeah, I think those holes are a bit small I hate it when the holes too small to poke his stuff into a oh, not a standard width and I'll tell you what, the binding posts don't even take four millimeter banana plugs nicely. I mean that's oh, that's actually quite a loosey-goosey fit in there and so is this one like this.

you know I know this is a B and C okay but you know, like that that is a real trip like this is not fair low vision but that is really loose. This one that doesn't have the the you know the fled things on it. that's just that just does not fit at all. I mean whereas on the Rygel for example it fits just fine.

So yeah, don't like the binding posts at all. They have a nice big clunk and power switch beauty. now that's soft power rubbish. all right.

So let's lift the hood on this thing. have to take the handle off the top. I Like that the handle is actually screwed into the metalwork on the top there. That's very nice.

It's not just like into there like the folded sheet metal case and then it's only held down here. So that's you know. It gives you a lot of confidence that it's not just going to break on you. So the quality in a power supply is all about the mains.

our transformer, the quality and brand of capacity Used the thermals, the internal wiring. you know, construction. It's nicely loomed and things like that. So let's give it a bill.

Tada. we're in like Flynn and got a nice big toroid here. Look at that, that's a monster. I Like that that's mounted vertically, but is that a shorter turn? Uh oh.

I Hope not. but apart. Anyway, we'll get to that nice cable loom in here. It's all you know.

It's all cable-tied held together and don't know where that one's going. that's that's flapping around in the breeze there. But they've got silastic down here. We'll take a look at the quality of the cats, but they've gone to the effort to put some silastic down there.

So here's this nice stock crossbar I was talking about with the anchor holes in there, so that's quite nice. and the thermals look and in fact it's very, very similar to the two. Another one whether looked at I'm sure it it's very similar. Anyway, the the fan of course here.

it's blowing out the back so it's sucking the air through the heatsinks here. So our power transistors are on the side here, so that's quite nice. That's all hunky-dory There's our mains board down there. We've got our mains wiring going over that looks very nice.

Looks like it's doing the business. We'll check out the mains, but that looks ok. It's going down to a screw terminal down there. Got a shake proof washer honor? I'm not sure but anyway, let's have a look at this transformer.

Now we thought toroidal transformers like this that have and they're a toroid shape hence their name. They've got a big hole in the middle there, a big donut and you always mount them down with a big screw going right through the middle and what they've got is two bits of sheetmetal work which are connected down to the chassis down here. Ok so they're not isolated, they're electrically connected. so this plate in this place is that both at earth potential.

and if you actually connect a bolt from one side to the other here to hold it in place, you actually create a shorted turn which goes through the middle of the toroid, around through the chassis and around through the other side. And that's a real trap for young players and incredibly bad design practice. But I think I might see in insulating Washoe right down in there. So I think they know all about that and they're doing the right thing.

So it's hard to tell about the quality of the toroidal transformer, but all looks ok. The wrapping all looks, you know, hunky-dory so I'm going to give that a passed. No problems whatsoever. shouldn't be any, of course not hum problems and things like that because there's no, it's not like a seek or laminate transformer which you have to be careful of.

If you don't laminate them properly then they can actually vibrate and you know that's where you get that. typical, you know sometimes you can hear that Harman instruments that actually comes from the mains transformer. You won't get that in a toroid so very nice to see a toroid there instead of a towards Generally you know a higher quality solution than a you know your traditional wire see core transformer and they've also got a rubber insulating mat in there which is very nice just so you know. no sharp bits from the middle work or anything can actually protrude through the wrapping and Pierce the windings and things like that and also lowering its electrical isolation.

So yet they've done it fairly well and there's a bit of attention to detail there. They put some Loctite on the screws holding down the only component on this thing that moves which is the fan and causes vibration. So excellent. but I don't see any rubber.

Um, you know, isolated vibration isolating washes in there? so I don't know I haven't never haven't turned this thing on. So I don't know if it's like a you know temperature controlled fan? I Assume it is. and I'm sorry to say Lille on brand caps don't cut the mustard really. Come on.

I mean you know a quality power supply that cost 500 bucks has one job and that's to use high quality caps and provide you know a long life linear power supply. Leland They're not the worst out there, but they're not a Panasonic they're not a Nippon chemi-con they're non niche econ. you know, like come on, they could have spent, you know I didn't dollar or two more for you know, really top quality caps so that's pretty disappointing. But they are 105 degrees C rated so that's okay LSM I presume that's the model I'm not going to look up the datasheet forum and they do have the separate mains earth wire going off to the Earth terminal on the front panel that goes over to the PCB Yes, they've got a split washer on there so that goes over It Pretty much provides a very low impedance path through the Earth terminal and that's what you want.

So they've done that decently. They haven't skimmed and if you can see down in there, they are doing temperature sensing on the heatsink. Geez, they've got that up. But there we go.

There's a little life thermistor right down there. bang on the heatsink. So they've got thermal overload protection. Nice, but you'd expect that.

I'm actually not that impressed with the mains wiring here. Why? Like they've cable tied it together? You might think. Ok, that's all. Ok, they've put some, you know, a Loctite type thing on the connector so they can't wear loose and stuff like that.

but the fact is, you're it's right up against the laser-cut edge on this metal chassis and that's I can feel that? that's a little bit. very tiny burrs, but nonetheless, you can probably see actually some of the scrape marks on the edge of the wire there. You can see that you should be able to see that. so that's what's caused by, you know, the laser-cut edge.

So that's the you know. like I would have put a big you know, insulating sleeve right over the whole bundle there, but they haven't done that and that's just tucked down in the side like that. so it's just not safe practice. I Don't like it.

it's you know it's They're probably going to get away with it, but you know in a quality supply you don't want to get away with it. You want to do it properly and that really should have a big insulating sleeve over it. Bummer and behold, the famous siglent rust. look later.

I Presume it's like laser-cut edge here. and we've seen issues with rust in siglent gear before. So yeah, no, it doesn't instill a lot of confidence, does it? If you've been watching my tear downs for a long time, you know? I'm not a big fan of just to-220 s flapping around in the breeze there. and that's what they're got.

Look, it's just, you know, stand freestanding off the board like that. I Don't like it from a vibrational point of view, especially in this orientation when it's not vertical. when it's horizontal like that. Is this things mounted on a, you know, mounted on a trolley out in some production environment or something? I've seen to-220 s a lot like that actually snap off just through vibration in a couple of months.

I You know, once again, they're probably going to get away with it, but it just shows a lack of attention to detail in that they probably. you know, maybe they ran out of space on the board, but it's I don't like it. It gives me the heebie-jeebies. One interesting thing here is the Ethernet and USB board.

Here's the Ethernet connector down here and you'll notice that the receiver is not. You know, the drive is not on that board. They're actually going through this unshielded cable here. This multi-way cable.

yeah, they've got a nice sleeve on it and everything. and that goes all the way over all the way with LBJ all the way over to the front panel where our trnsito Ethernet transceiver is down there. So yeah, see, there's our output transformer. So once again, you know they're getting away with that.

I Mean you know, like these are not proper are twisted pairs either. like you'd get on a proper Ethernet cable. So if you wanted to do that really professionally, you'd actually put an Ethernet connector on the back here and then you'd actually have a proper Ethernet cable running over to another, a matching Ethernet connector on the back here. Then you plug it in and then you know you'd have another one coming out.

And you know, yeah, I Don't know. Maybe I'm being a bit nit picky. Now you notice that on this Heatsink here, we've actually got there's our bridge rectifier. Okay, input bridge rectifier.

but we've got two power transistors on this one, whereas the one on the other side, we've only got a single power transistor There, it is down in there. Why is that the case? Well, this is a triple output power supply. so clearly there are running the five volt output here. All this us switchable.

It's not adjustable, it's switchable, so that's and has its positive and negative points. Anyway, they're running that one from this secondary heatsink over this side. So in theory, in theory are this the power output from here is coupled into the heatsink. For example: I Am going to assume it's Channel one here, so that in theory you'll get less out into maximum power output from Channel one than you would from Channel 2, but the specs are the same, but that heatsink will actually heat up more than the other one for this one.

But as long as you design that in, there's no problem with that. I'm just pointing it out and sorry that I'm not going to take whole thing apart. I Don't really want to go to that sort of effort, so it's a bit bit dodgy on some of the camera angles here. Anyway, this tap on the transform of the yellow wires.

that's clearly the tap for the third channel output. and there's our full wave bridge rectifier for the user's individual diodes for that third channel. so they're not putting those on the heating because that doesn't have the same power output requirement as that channels one and two. So no problems there.

And get away with that. Fine and dandy. By the way, our mains input board. No real problems there.

There's no fusing on this board because that's a part of the IAC input connector on the back panel where it's fused. They've got their isolation slots in there. You know there's no you don't need that common mode chokes and things like that for a write. Such a linear power supply.

So yeah, that's all par for the course. No problems of it at all. And I said a big thumping power switch. Nice.

And they've got some PTC's in there. Very nice just for this. It looks like an auxilary winding coming from the transform. You can see a tiny little lob read: discrete bridge rectifier there, so you know that's not too shabby at all.

Well, if you're a bit disappointed about the input capacitor as well, check out the output capacitors. these are Rubicon's there you go. so that's at. the Rubicon are a decent brand capacitor so the at least on why they've you know use Rubicon's on the output.

We can't use Rubicon's or you know some better brand on the input night I don't know. but then they've mixed those up with that. Leland's here once again that you know these. Taiwanese Brent and Ally LAN are okay.

um, kinda sorta. But yeah, it's just like why they mixing those in. You know, like there's a Rubicon output caps? Well, why not make everything else Rubicon Don't get it. And for those processor aficionados playing along at home I know you're out there.

we've got an STM ARM processor. So fairly grunty. so this is probably running some you know, like Linux OS or something in a power supply. Yeah, it's like Mm-hmm but yeah, okay, whatever.

but you know they've got Ethernet it's all PC controlled blob of networking, the whole jazz. It's got a graphical do you know display, an interface and graphene and all that sort of stuff. so you know you're kind of sort of have to go a bit. you know, a high-level OS there.

There's not not much, not a huge amount of choice really, so that's fine. And they do have PCB mount tough users directly soldered on you know, lead, axial lead ones soldered onto the board down there. so they're actually doing that a few time. Well, they've got one for each channel basically.

and they've got some on the front too. and they're doing that on the front panel as well right there. So once again, another resettable refuse their Ptc there and a couple of more to-220 s just flapping around in the breeze. actually.

sorry, silly may I stand corrected. These Rubin con caps here aren't actually for the output, these are. these look like filtering for the main power supply for all the electronics and stuff like that. Of course the minimum output capacitance because in you know, in a in an adjust like a adjustable current up how slow you want the output capacitance to be absolutely minimum possible.

So there's the third channel for example, which is the fixed voltage output. Well, that one doesn't yeah, that one would have a current limit I think I don't know I haven't actually tried it anyway. Um, small amount of output capacitance but once again, that one is a Rubicon. But there's an output for channel 2 and these are not Rubicon caps.

so these are Lille on. So yeah, there you go. They've actually got a fair bit of output capacitance there. You'll notice that the the reverse protection our diode there's straight across the output.

pretty beefy. They've got that also down here on the third channel as well, so that's common as much. And there you go. You can just see our output current shunt resistors there I Don't know whether they're high side or low side, but yeah, they got two of them if they work those in parallel.

Not entirely sure, but yet, this is a precision power supply. As I said, 1 millivolt, 1 milliamp resolution which is quite, you know, very impressive on a 30 volt 3 amp output capable supplies. so it's going to be reasonably high-end ADC in there somewhere. Is it one of those puppies? I Don't think the Arm STM Um.

processor has a high enough resolution ADC even if it has one. and ha, this is where the magic and the performance comes from. And analog devices. ADR 77 92 This is actually a pretty decent little beast.

It's a three channel 16-bit Sigma-delta convert. It's got a built in 4 ppm voltage reference, it's got built-in differential amplifiers and all sorts of jazz, and they've also got a Adr-03 that's a pretty recently Schmicker 3 ppm 2.5 volt voltage reference as well. So they've got some decent hardware in here. so I don't doubt that it actually meets its Us specs and performance targets and accuracy and stuff like that.

So yeah, thumbs up there. And they've got a whole bunch of sharper PC Eight, One, seven optocouplers there. that's to isolate all the data required. Nice.

There's one thing I don't see around the processor here and that's a JTAG header. Is that the puppy up there on populated perhaps? And there's all our relays in there to do the switching for our series and not parallel functionality on the front where you can join the outputs and get you know, double the capability so you don't have to physically wire them. you can. and then the voltage of track and things like that.

So that's nice. But they're Yeah, they're not exactly name-brand relays, they use the same ones over here and well I Yeah, offhand. I Don't know who makes those, but me. whatever.

In case you don't know how linear power supplies work when you've got a 30 volt or 3 amp output range. Okay, that's a lot of power. And if you're got your voltage output set to 1 volt for example, and you've got a 30 volt input, you know you've got to drop 30 volts at 3 amps. That's a huge amount of power you know dissipated in your output power transistor here and you're heating.

So if you depends on the voltage rains, they're actually going to switch in different taps on the transformer so you know they might have like a you know a 8 volt tap for your low voltage. So if you set your output voltage to 5 volts air, it might switch it to say the 8 volt AC tap and you don't nearly dissipate as much power in your output power transistor or you and your heat sink there. So you know when you go up to 12 volts output, they might choose a you know, 17 volt tap or something like that. And when you go to full 30 volts output when you set that at, they might switch in 30 volt AC tap or something like that.

And for those playing along at home, switching train is an IRF P150 end MOSFET And now I Remember where I've seen very similar construction here with the heat sinks. It's almost a identical arrangement. It set for the toroid transformer here had a linear supply. I'll link in my Attend Power Supply teardown.

That was a horrible oh, that was awful power supply both in terms of functionality. It was awful to use and the construction quality was pretty terrible as well. This sequence, actually, you know it's quite reasonable. It definitely streets ahead of the Attend supply, which was absolutely horrible.

It used a linear transformer, but curiously, the Aten one had. Actually, it was a precision not power supply as well, but had lots of horrible problems. But it actually had on the heatsink, some thermal cutouts. It actually had thermal mechanical cutouts on there I Mean you know signal? You don't have to have those.

I Guess it's just a cheaper and simpler way of doing it cylinder, doing it electronically. here. they've got you know, a temperature sensor directly on there and then they can electronically shut the thing down. so that's you know.

Technically, that's actually better, but you know if you're sensing element fails or whatever you know though, those mechanical thermal cutouts, you know, really old-school kind of thing. but the attend one actually used Nippon chemi-con capacitors? go figure. and that one was really built down to a price and really shoddily constructed, so the sickling is much better in that respect. So overall, I've got to give it a pass.

It's not too bad like you know, but there's just a few little niggly things in there. And you know, as I said, I would have preferred some better quality art parts in there, but it is reasonably neat construction. It's I Do believe it's going to meet its performance. It's got the IADC and the reference in there.

It's doing the business and all of the sense in everything's on the front panel PCB down here, so we don't have to dick around with that if you I'll have to link in there. I Go our DP 832 Power Supply teardown and it actually had meant in quite a few design issues in terms of that sense in the voltage and things like that. So it actually use discrete wiring through to the front panel whereas this actually is, you know it being quite neat. they've actually put a bit of thought into, you know mounting it all on the one front panel board like that, so that's not too shabby.

and there's silastic things down, and you know it. It's certainly certainly a pass, so you know a decent quality art toroidal transformer in the thing and just let down by a few smaller touches. but generally. um, I guess I'm fairly happy with that.

All right. So let's power this puppy up and maybe we can put a load on it and check out its our thermal performance. perhaps. So here we go.

Or booting straight into it. look at that nice display on it. Love it. And that fan is actually going.

But I'll tell you what, with no load on this thing, it is practically silent, so it's got to have our temperature control. I Expect the fan to really increase when we are fully load this thing down, and then some annoying user interface things like this: I Have to do a separate video on using this thing. But look, you turn the voltage up, voltage setting over range. Why tell me that? Why flash that up? It's just stupid.

Just stop at 32 volts. like just stop there I Know it's not going to I Don't need to be warned. Give me a break. Well, I'll tell you what.

I'm switching this voltage all the way through the range I cannot hear these relays switch I cannot hear the range switching at all I swear I've put my ear right up to it, can't hear a thing and as I said, go to plug these up. another plugs in here. They really feel loosey-goosey doesn't instill a lot of confidence in me at all. I mean look, I've just got you know might resist a load on there and you'll notice that the currents flapping around in the breeze.

If I actually look put force on those beings those banana plugs so that they're doing that, look I get a You know, a perfectly nice, stable current I leave them loosey-goosey and that's not making good contact Anyway, you'll notice that when I change this I actually had that set to four volts there. If I have it set to five, you'll notice that it actually Oh doesn't do it there. Let's go to four. It'll actually change between.

So when you're turning the knob, it'll be the set voltage. Okay, but then once you're a second later after you release it, it'll be actually the physical output voltage. which is fine. That's I'd like that.

but the thing is like they've got this huge display right. All of this display to their advantage. but they waste all this space with this stupid timer thing. Most of the time you're not going to use the timer.

Okay, so get rid of it until you need it and then have you know set voltage, set current, and then display like maybe even a tiny Vaught a tiny font up here. you know set voltage, set current and then have your big displayed. You know your actual output voltage in your actual output current, and your actual output power. You know like I it's a power supply.

You want to know this information? You want to know what you set it to. Now in terms of thermals on this thing, I'm actually shorting the outputs are just running the thing at a full pelt at the moment. But I'm having to look at the front panel here and this is as I said, these two big filter caps. There's a bridge rectifier tucked away in there.

It's got its own fuse. That's for the electronics. I Believe in that bridge rectifier in there. Check it out.

90 odd I'm getting a peak of like over 90 degrees for that bridge rectifier. Sorry about the glare there. Wow, that's not. It's not terrific at all.

That doesn't instill a lot of confidence in me. and what I'm doing is I'm running both outputs here I'm sort of like a shorting them out and I ran them up to 32 volts. but once again, I still don't know without actually getting in there and start measuring stuff, probing around and around. I don't know where the actual voltage taps are because usually you'd put it like at the worst possible tap.

So I can actually put it down to say one volt on both channels here and then that you know that might be near enough to sort of worst-case worst case power dissipation because it's got to drop almost the full would ever transform a tap voltage down to our one volt output. And then we shortened the thing on the output. So yeah, let's give it a bell. So this is actually really kind of hard to get.

But if you have a look in there like sorry about the like, the transformer is not black anodized so it's not going to be an accurate temperature so it's going to show up cool. But let's look at our Silicon down there. that's our output transistor that's the hottest and I was getting a peak of just over a hundred. Yeah, there we go.

Hundred hundred degrees on the power transistor. so that's that's pushing it. But that is worst case. it's still within margin.

But yeah, and yes, by the way, at full tilt, Yes, that fan does. Come on. It's yeah, it's noticeably loud, but hey, that's par for the course on these types of power supplies. Okay, I Finally able to get the transformer taps on this thing.

It you know the output has to be on before it will switch the transformer tap. So let's go down here and clunk once you get to eight volts and switch back down from seven. There we go. So that's the first tap and then 16 down to 15 24, 22.

So 23 24 And that's it. There you go. three taps. Okay so what I'm going to do now is use my famous power supply killer here.

Other became Precision 8500 electronic load that I have managed to kill a production power supply with before. When you set it to constant resistance, you can actually get this thing to oscillate between constant voltage and constant current mode. So I've got it set to eight volts which is like the minimum of the tap. Okay so the next tap so it's actually so we switch to the next tap so this will be dissipating the most about amount of voltage across the output power transistor.

I've got my resistance set to one Ohm here and we'll give it a bill. Listen to that. There we go. It's pretty horrific.

It's pretty horrific I don't see any magic smoke escaping and it's switching the input range current as well the transformer tap as well I wouldn't like to leave there going all day every day I think it will eventually die, but yeah, let's turn that off and it's started working again and we can go back to say 1 amp constant constant current for example and switch that on. Ah sorry yeah, oh I'm sorry I had already adjusted the current here so I've got to go in here and up the current. There we go. one amp yep, it's working a treat and I switched it to like the 19 volt range and it's even more violent now.

Wow, it's really not liking that, but hey, it's surviving. Nothing's dying. So beauty and I went out for a bit. came back.

look at this by default. It looks like it has a bloody screen saver. Why? this is just insanity. It's a bloody power.

I assume I push that to get it back. It's a bloody power supply. Just leave that to slay there. Unbelievable.

So there you have it. Hope you enjoy the a little quick look inside the Sieglin SPD a 3300 X-series precision programmable DC power supply and I'll have to do a follow-up video of this of course, actually playing around with it. Maybe a shootout comparison with the Rui Goldy P83? - perhaps? So yeah, well stick around for that, even though I haven't planned to shoot it yet. but maybe I will anyway.

if you liked it, please comment on the video, give it a thumbs up and all that sort of jazz. Discuss it on the forum, you know, follow me on Twitter and buy my merch and let's subscribe and all that stuff. I'm going to say as a Youtuber to you know, stay in business. Catch you next time you.