xbox-scene.com archived forum

Please login or register.

Login with username, password and session length
Advanced search  

News:

xbox-scene.com forum restored.  registration disabled.  thanks to xboxexpert for the db dump and netham45 for cleaning it up!

Pages: 1 [2]

Author Topic: Experts Needed - Slim With No Power  (Read 189 times)

RDC

  • Guest
Experts Needed - Slim With No Power
« Reply #15 on: September 06, 2011, 08:46:37 PM »


The SOT25, SOT   23-5, SOT5, SOP5, TSOT 23-5 and TSOT-5 are all pretty much the same thing, so   narrowing it down by just one package style really can't be done with   this thing, but, I finally found something that has what I believe to be that pinout, in that package (SOT 23-5) and makes sense, but again I'm not 100% on it as nothing crosses to the markings on your chips, so if you or anyone plans to try it out do so at your own risk, well risk to the Slim anyway.
 
 I had a longer look at your pics, and that Inductor was the key. At first I thought it was there just for the output, like a filter, but   then after looking at it more I decided to get away from the strict   Regulator definition line of thinking (LDO type) like the older 360 used. First off they don't really have the   current being that small, and second there wouldn't be any real need for that Inductor there   if it were an LDO type. So I tossed that line of looking for   parts out the window and went with something that could output more current, as well as be more complex because of that Inductor, since simple wasn't   getting us anywhere.
 
 Now the kind of Regulators that use an Inductor are Switching (Buck -   Boost type) and since it's going from 5v to 3.3v or 1.8v then it's a   Step Down, and I still believe it's Adjustable because both seem to be the same part, but are for different voltages. More specifically it seems to be a Synchronous Step Down   Converter. Which I believe could be the SP6669AEK-L from Exar.

http://www.exar.com/...RevG_120208.pdf

Again, this is all pretty much a wild stab in the dark, and for right now just my best guess at the thing. It may need to be rated at 1A like the older Regs were, but I'd doubt it as that 5vsb was only 1A and fed both Regs on the older board, so the Exar (600mA) might be more than big enough, again if it's even a suitable replacement. I'd personally give it a shot if it were mine and I was messing with the thing, but yet again, it's only a guess as to what the part may be since it doesn't cross to anything yet.




Edited by RDC, 07 September 2011 - 04:48 AM.


Logged

pg0d1n

  • Guest
Experts Needed - Slim With No Power
« Reply #16 on: September 07, 2011, 04:08:14 AM »


The SOT25, SOT   23-5, SOT5, SOP5, TSOT 23-5 and TSOT-5 are all pretty much the same thing, so   narrowing it down by just one package style really can't be done with   this thing, but, I finally found something that has what I believe to be that pinout, in that package (SOT 23-5) and makes sense, but again I'm not 100% on it as nothing crosses to the markings on your chips, so if you or anyone plans to try it out do so at your own risk, well risk to the Slim anyway.
 
 I had a longer look at your pics, and that Inductor was the key. At first I thought it was there just for the output, like a filter, but   then after looking at it more I decided to get away from the strict   Regulator definition line of thinking (LDO type) like the older 360 used. First off they don't really have the   current being that small, and second there wouldn't be any real need for that Inductor there   if it were an LDO type. So I tossed that line of looking for   parts out the window and went with something that could output more current, as well as be more complex because of that Inductor, since simple wasn't   getting us anywhere.
 
 Now the kind of Regulators that use an Inductor are Switching (Buck -   Boost type) and since it's going from 5v to 3.3v or 1.8v then it's a   Step Down, and I still believe it's Adjustable because both seem to be the same part, but are for different voltages. More specifically it seems to be a Synchronous Step Down   Converter. Which I believe could be the SP6669AEK-L from Exar.

http://www.exar.com/...RevG_120208.pdf


Again, this is all pretty much a wild stab in the dark, and for right now just my best guess at the thing. It may need to be rated at 1A like the older Regs were, but I'd doubt it as that 5vsb was only 1A and fed both Regs on the older board, so the Exar (600mA) might be more than big enough, again if it's even a suitable replacement. I'd personally give it a shot if it were mine and I was messing with the thing, but yet again, it's only a guess as to what the part may be since it doesn't cross to anything yet.



I did not know about those packages. I guess that's why you're the expert  biggrin.gif

Thank you so much. I strongly believe that is the part number by reading the datasheet. I just ordered a dozen of them (hopefully it's the right part). I ordered the SP6669AEK-L/TRR3

I'll keep you posted on how it goes when they come in.

There is another user on XE that has the same problem. His are shot too. So obviously, this is something that we will see more in the future.

Thanks,

Phil




Logged

RDC

  • Guest
Experts Needed - Slim With No Power
« Reply #17 on: September 07, 2011, 04:53:39 PM »


I doubt the Regulator is the only problem, but if it does fix it then later versions of the Slim will have that section revamped for sure. Odds are though the issue is on that 3.3v or 1.8v standby rail loading them down.




Edited by RDC, 08 September 2011 - 12:54 AM.


Logged

pg0d1n

  • Guest
Experts Needed - Slim With No Power
« Reply #18 on: September 07, 2011, 05:00:53 PM »


I also believe that there is a problem down the 3.3V rail. Problem is where to look.
We'll se when the parts come in.

If it doesn't fix it and I can't find the problem, well, I paid $60 for it. Came with a 250GB hard drive and a wireless controller.

Would rather fix it, but worst comes to worst, I know I can double my money easy.




Logged

RDC

  • Guest
Experts Needed - Slim With No Power
« Reply #19 on: September 07, 2011, 05:16:26 PM »


I'm sure the core of it's not far off from the older 360, which means most of that 3.3vsb line is for powering the RF (RoL) board, which has already been tested as good, and then the Southbridge, which there's no point in even trying to repair unless you have access to that kind of equipment and a good one to swap it out with. It could be something like a shorted SMD Cap on that 3.3vsb line as well, like you said, where to start looking for that needle in a stack of needles is the problem, and even with a schematic troubleshooting a motherboard is one of the worst things to attempt. Good luck with it.





Logged
Pages: 1 [2]
 

Page created in 0.144 seconds with 17 queries.