Power supply build quality pictorial. part 2

[Behemot]

For me, before I've read that document I posted here, I didn't even know there is such thing. You know that, you won't see it if you are not looking All I have encountered so far were the BGA cracking problems, and believe me, it was enough for me already. Now I learned about whiskers some time ago. What else will come? For absolutelly useless crap? We all know lead is pretty much stable when in compounds.

As the document clearly says, the saved amount of lead in solder is just tiny fraction of all lead which is not recycled ever. So all we have are negatives. I can see not a single one positive. So what's wrong with this world??

[Wester547]

A bit more on-topic...

This is far back but a over a couple years ago a couple of Hipro 250W Dell PSUs were posted in this thread by momaka and larrymoencurly. momaka's had Passive PFC (HP-P2507F3P), larrymoencurly's did not (HP-P2507F3R). What I noticed is that instead of the usual two ferrite coils in the transient/input filtering section of the PSU that Hipro use (in that design, at least), there was a ferrite coil and what appears to be a transformer or filter of sorts, going by the designation of 39EEL07701 or something like that. You can see it in the left corner of this image. Does anyone know what it's for and if it alters the single switch topology of those PSUs at all, or if it improves upon the transient filtering as opposed to just using two ferrite coils (I have an older version of the HP-P2507F3P which has the same configuration so I'm curious)?

[Behemot]

Isn't it just additional filtering? I see quite often traditional EE "transformer" being used as just supressor. I think there is not that much difference whether you will use toroid or EE core?

[Wester547]

That's what I thought it was but I wanted to be sure.

One more question...

This part in front of the fan in this Newton Power/Dell 200W... (that says DET033 at the end of it)

Is something of a suppressor or filter as part of the transient filtering state to combat against power spikes/surges/outages, right?

[Behemot]

Yep, another coil.

[tom66]

Such a device is only effective kHz or above. No influence at all on power sags, spikes or dips, or other transients. That is the job of the bulk capacitors. It's only for RFI pushed into the power line by the PSU (conducted emissions.)

[pdavid]

Here is a small Hipro form a pile of "e-waste" Dell P3 systems. We still have a few of these at work
According to the label it's a 150W unit. Looks more capable. Has Matsushita and Su'scon caps. These are pretty old but working to this day.

[momaka]

^ It will probably do 200W with no problem. And look at that - seems as if the 5VSB is also driven by a UC384x variant. No 2-transistor self-oscillating laziness.

[Wester547]

Originally Posted by momaka

^ It will probably do 200W with no problem. And look at that - seems as if the 5VSB is also driven by a UC384x variant. No 2-transistor self-oscillating laziness.

This may sound noobish but how can you tell whether a 5VSB circuit is UC384x driven or not if there is a UC384x chip present in the PSU, on the primary side? I ask because Jonnyguru's review of the notorious Bestec ATX-250-12E shows that it has a UC3842BN chip soldered to the primary side but also has the infamous two-transistor 5VSB circuit (a TO-247 MOSFET - STMicroelectronics W7NC90Z - is used as the main switcher and a 2SC4020 TO-220 transistor is used as the 5VSB transistor).

[momaka]

Actually, now that you asked, I think I might have made a mistake about that statement. I just saw two 8-pin DIPs and ASSumed both were UC384x (one for main power supply and one for 5VSB). But now I see there is also a second small transistor next to the main 5VSB transistor, so this may as well be 2-transistor circuit.

But generally, if you see only one UC384x chip on the primary size and the PSU is forward-converter topology, you can safely assume it is for the main power supply and not for 5VSB.

[pdavid]

Originally Posted by momaka

^ It will probably do 200W with no problem. And look at that - seems as if the 5VSB is also driven by a UC384x variant. No 2-transistor self-oscillating laziness.

So, to clarify this. The standby uses a 2SC3866 fet driven by a 2222A. The other 4 pin ic is a KA393...

[momaka]

That's a bit disappointing coming out of HiPro. But I think everyone did it more or less back then. I do have a few ASTEC power supplies that don't use 2-transistor and they are quite old. But they have other weak points (inefficiency and loud fans being the two most noticeable).

[PeteS in CA]

The KA393 is probably a version of the workhorse LM393, a dual general purpose comparator.

[Shocker]

Overview.jpg
To fix this will take a bit more than recapping, but none of the extra steps are too difficult:

• Move the fan controller so it isn't so dangerously close to the EMI filter
• Swap L and N at said filter (it's installed with the IEC pins backwards from the PCB markings, so the connection of the wires according to the markings swaps L and N, which means I have to correct polarity by putting them "backwards")
• Install proper Y-class caps (the X caps are the proper type)
• Install a single-piece bridge (also, the 4 x 1N5408s take up space that could be used by another X-cap)

D209L (=13009L) main switchers, ERL-35 main transformer, SBL3040PTs on +3.3V and +5V (1 each), F20C20C on +12V, 1N5844 on +5VSB, pi coils on all outputs. With all of these you'd never guess who made it.

Connectors: ATX 20+4, ATX12V 4-pin, MNL x4, FDD x2, SATA x3

The label says +3.3V 28A, +5V 35A, and +12V 24A. I think this would do about 300W continuous, after repairs.

[c_hegge]

Originally Posted by Shocker

With all of these you'd never guess who made it.

TB markings on the second line of the transformer = TeBao = Sun Pro.

[Behemot]

Isn't that another version of the famous ATX-550JSP or somet'ing like that? Black thing with 12- or 14cm fan, 550 W labeled?

[Behemot]

The review is still not out, but I think I can share the pics

Corsair VS450 - CWT
Interesting thing is this CAP004DG on one X cap, providing savings on it's safe resistors. GBU406 rectifier. All crappy caps, 180 uF/400 V AiSHi(t) on input; it hovever has CM6805+CM03X which claims to have advanced PFC/PWM requiring cheaper cap and silicon.

Some cheap chinese copy of 13N50 on PFC with PFCD86G diode. Switchers are some 10N50. This all has high Rds(ON), that's the low efficiency of it hitting 80 %, but average is under 80 % thus it has no certification.

TNY177PN for +5 V SB, other crappy caps - small JunFus arround which may be baked by the chip, C(r)apXon2200+1000 uF combo on output. However it has nice beefy diode with nothing arround, so it may stay cool.

Other secondary: double STPS20L60CT/+12 V, STPS30L45CT/+5 V and finally magamped MBRF2045CTG for +3,3 V. Sitronix ST9S429 aka Unisonic Technologies S3515 secondary monitor. Mostly 2200+1000 uF C(r)apXon/AiSHi(t) combo.

It has actually very good voltage control on crossloading, voltages varied even less than on combined control (aprox. 2 % vs 3 %). Ripple is within 60 % of spec (very low on +12 V). BUT. The -12 V rail may be very problematic. Loading it with 0,36-0,38 A of mine Papst fan between -12 and +5 V made it oscillate like hell. I haven't checked at 0,3 A precisely but I think it may have strong problems as well. It's feedback is connected to +3,3Vs voltage-wise and to +12Vs current-wise.

Built quality is not that good providing it's the cheapest Corsair has, but it's not actually dangerous or something.

[mariushm]

Nothing unexpected, it's supposed to be a China only (230v) power supply, but I heard they wanted to start selling it in Europe as well.

[Behemot]

They are selling it here for some time, I guess you have somewhat old infos

[tom66]

I don't see that thing doing 450W for very long. Those heatsinks are not very big.

The 180µF primary also means you'll likely see 100/120Hz ripple on the output near maximum loading. See it on a lot of PSUs with undersized primaries....