Vantec 520w 12v mod? No vsense line [Archive]

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BMORIN

09-20-2004, 05:04 PM

Vantec 520w 12v mod? No vsense line

I've done some psu mods, but this psu doesn't have a vsense line to either the 12v or the 5v (only the 3.3v). How can I raise the 12v line without the use of a vsense line?

Hell-Fire

09-21-2004, 11:28 PM

Look on the inside of the psu to see if internal pots are already available.

If not, then you will have to look to see what controllers are in there and we can go from there. Try to read the markings on the chips, and take pics if possible.

celemine1Gig

10-10-2004, 09:28 AM

Just as a sidenote: AFAIK, these Vantec PSUs are based on TSP=Topower PSUs, just as the GlobalWin and Tagan PSUs. So it could be very interesting for people with these PSUs (for example me), too. :D

Hell-Fire

10-10-2004, 09:35 PM

Waiting on pics.

celemine1Gig

10-11-2004, 05:12 AM

I'm going to mod my 420W TSP triple fan PSU with new Panaflo fans, as the original fans started to make noise (they are definately crapping out :D ) and then, I'll take enough pics. ;)

celemine1Gig

10-16-2004, 01:13 PM

Pics are ready. I'll upload them later and do some research (datasheets and so on). Hopefully, we'll be able to figure out the mods. That would be awesome. :toast: :banana:

celemine1Gig

10-16-2004, 04:21 PM

PSU taken apart:

http://www.forumdeluxx.de/gallery/data/500/4423TSP4.JPG

celemine1Gig

10-16-2004, 04:21 PM

chip 1:

http://www.forumdeluxx.de/gallery/data/500/4423TSP3.JPG

datasheet:

http://www-s.ti.com/sc/ds/tl3842.pdf

celemine1Gig

10-16-2004, 04:22 PM

chip 2:

http://www.forumdeluxx.de/gallery/data/500/4423TSP2.JPG

datasheet:

http://www.addmtek.com/pdf/AMC34063.pdf

celemine1Gig

10-16-2004, 04:22 PM

chip 3 and 4:

http://www.forumdeluxx.de/gallery/data/500/4423TSP1.JPG

datasheets:

http://www-s.ti.com/sc/ds/lm339.pdf

and

http://www-s.ti.com/sc/ds/tl494.pdf

celemine1Gig

10-17-2004, 01:08 PM

Well, it goes on. I had a look at all the datasheets and I think that there are only 3 interesting chips out of the 4 that I posted the datasheet links for.

Those 3 are the following:

Texas Instruments "TL494CN"

Texas Instruments "TL3842P"

and

ADD MICROTECH CORP. "AMC34063M"

All three have Feedback lines. So I assume that each chip controls one voltage rail. One for 3.3V, one for 5V and one for 12V.

I'll try to measure the VCCs (output voltages) on these 3 chips and then I'll add a 1K poti into the 3.3V feedback line, a 5K poti into the 5V feedback and finally a 10K poti into the 12V feedback line. Hope that works out. That would be really great.

Wish me luck guys!

PMM

10-17-2004, 02:57 PM

TL494 pin 1 to ground via resistor same chip as in my Qtec 550W
that raised the 5/12 together

celemine1Gig

10-17-2004, 03:58 PM

TL494 pin 1 to ground via resistor same chip as in my Qtec 550W
that raised the 5/12 together

That's really good news! THX!
Now I only need to find out what the other chips do. But hey, well, I don't really need to know as the 3.3V rail has a sense line and that makes it complete. ;)

Wait, hold on a minute...
Isn't it pin3 to ground. Pin 3 is Feedback, whereas Pin1 is for Input Voltage. :stick: :confused:

PMM

10-18-2004, 10:24 AM

nope pin1 ;) there is a Qtec 550 thread in this forum has a pics ;)
few down from this.

Pin 1 is part of an error amplifier

http://xtremesystems.org/forums/showthread.php?t=12166

scroll down a few posts

celemine1Gig

10-18-2004, 10:44 AM

I already read that thread, but I'm still sceptical. I'll try pin3 and see what happens, because normally, a Vmod is done by manipulating the feedback line. And if I'm not mistaking, Feedback and the two error Amplifiers together build one signal, so it should also work with Pin3. According to the "functional block diagram" (in the datasheet), it doesn't matter if you change Feedback, 1In+, 2In+ or 1In- or 2In-, as they all lead to the "Reference Regulator" together as one single signal!

PMM

10-18-2004, 11:24 AM

I think the ref voltage feeds the feedback pins 14 to 3 I think that defines the
Voltage I think grounding would drop it.

Could be wrong though... It was a long while ago when I did it, but there was a
reason why I went pin1 as most normal mods work off the feedback might even
have been to overcome the Overcurrent Protection really not sure now.

I posted Pin3 to start with but had to nip into my vmod archieve to double check
as I had a niggle It was not the feedback I was using.

Good luck I'm sure you'll crack it... Just make sure you fully drain the thing before
working on it don't want any one electricuted off those capacitors.

celemine1Gig

10-18-2004, 11:53 AM

celemine1Gig

12-12-2004, 08:30 AM

Well guys, there's good and bad news. I finally had the time to vmod my TSP P4 420W PSU and initially everything went fine. :toast: Had the rails adjusted to over ~13V and ~5,5V and ~3,6V. Then I shut the power off to try something else.

Afterwards it never powered on again. :stick: (only made changes that had wrked before!). :confused:

Fortunately I had it running unconnected, that's to say, not mounted in my case. I had it lying on my couch, jump-started with PS_ON-GORUND and only one 12V fan connected. So, nothing else got cooked. :)

I'm really sad, as this PSU was really good. :(

Edit: OK, I thought about it for a few hour and I think the chances are good, that only the fuse burned up to save the PSU, when I adjusted something to a too high level. I don't know, but I'll try that for sure. That'll take some time though, because I have to dissamble the whole PSU to get to the fuse. :)

celemine1Gig

12-12-2004, 03:54 PM

Here are some preliminary pics:

http://www.forumdeluxx.de/gallery/data/500/4423TSP-Mod1.jpg

http://www.forumdeluxx.de/gallery/data/500/4423TSP-Mod2.jpg

http://www.forumdeluxx.de/gallery/data/500/4423TSP-Mod3.jpg

http://www.forumdeluxx.de/gallery/data/500/4423TSP-Mod4.jpg

http://www.forumdeluxx.de/gallery/data/500/4423TSP-Mod5.jpg

Playful_Buffalo

12-13-2004, 09:56 AM

what rail is the first pic? :confused:

celemine1Gig

12-13-2004, 11:00 AM

what rail is the first pic? :confused:

That's the 12V-rail at default. Remember I had the PSU running without any load (except for that one fan that I mentioned). This PSU gives higher readings when it's fully connected to a PC and under some load.

So the 13V pic would equal about ~14V when connected to the MB and stuff, I'd roughly say. I don't know how high I could have gone because I just stopped there. There should be a lot of headroom.

celemine1Gig

12-29-2004, 05:36 AM

OK, I'm really happy again. Got a new fuse today and the PSU works like it had never stopped working. :D

Will finish my mods the next days and then it's time to rock!!! :toast:

celemine1Gig

01-17-2005, 01:26 PM

Another little update:

Now I definitely know how the mods should look like on that PSU. The only problem with this TSP 420W unit is, that I seem to have messed up the overvoltage protection in the process of finding the right vmods. Sometimes the unit starts up, but sometimes it doesn't and the readings are very suspicious (they change without changing resistance and so on). Well, I'll try to clear that in a few weeks.

Won't have time to work on my computer related stuff until the beginning of february as I have to write three tests until 31th january.

In the meantime I got me 2x 520W Topower PSUs (same manufacturer, as Topower=TSP) and nearly identical PCB. Will perform the vmods on at least one of these units. If this will work out OK, I'll perhaps do the vmods on my Tagan 480W PSU, too.

Stay tuned guys and keep on modding!

Greetings from Bavaria

Ingmar :) :toast:

Edit:
Working on it again, since today! Will keep you updated!

Edit:

Another short update. I think I really borked the 420W PSU. DAMN! Worked on it yesterday. Tried to fix it, double checked everything, but it's still not working. Just giving a clicking sound, when being turned on. :mad: :stick:
But hey, at least I know how I f***ed it up, thus I know how to aviod it on the other PSUs. Will work on the other PSUs soon. ;)