EEVblog #828 - Siglent SPD3303X Precision Lab PSU Teardown

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 tránsito 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

Channel: EEVblog

Views: 259,999

Rating: 4.8603144 out of 5

Keywords: Product Teardown, power suppy, psu, lab, precision, siglent, rust, review, teardown, pcb, thermal, design, measurement, SPD3303X-E, SPD3303X

Id: mdOauVzY9OU

Length: 31min 49sec (1909 seconds)

Published: Wed Dec 09 2015