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Old 02-22-2019, 06:53 AM   #1
berthfield
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Question Help identifying power ic?

Good Day,

I was recently presented with a inexpensive DVR that had a short in its power supply. After searching I was able to isolate the issue to the 5v rail, specifically a 6pin IC with the markings DDAAC. It seems to be some form of power ic or a buck converter or sorts.

I have been searching but cant seem to find a way to identify these ICs, could you point me in the right direction please. Attached to this post is an image showing a similar circuit on the board that is unaffected.

Thanks in advance.

Attached Images
File Type: jpg UoY4xCi.jpg (143.5 KB, 4 views)

Last edited by Per Hansson; 02-22-2019 at 02:44 PM.. Reason: Offsite image uploaded & link fixed
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Old 02-22-2019, 09:12 AM   #2
R_J
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Default Re: Help identifying power ic?

I can't see anything but an [X]
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Old 02-22-2019, 11:41 AM   #3
PeteS in CA
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Default Re: Help identifying power ic?

Either img tags are not working, or vBulletin is not recognizing the imgur page as an image, https://imgur.com/a/2oQ3LXE .

I can't see clearly any IC such as berthfield described, but there is an electrolytic cap in the pic that clearly is swollen and vented.
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Last edited by PeteS in CA; 02-22-2019 at 11:42 AM..
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Old 02-22-2019, 12:34 PM   #4
R_J
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Default Re: Help identifying power ic?

U4 looks like a sot23-6 LDO, Maybe post the model number, maybe there is a schematic around
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Old 02-22-2019, 02:45 PM   #5
Per Hansson
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Default Re: Help identifying power ic?

Quote:
Originally Posted by PeteS in CA View Post
Either img tags are not working, or vBulletin is not recognizing the imgur page as an image, https://imgur.com/a/2oQ3LXE .
Well, it's because it's a link to a webpage, not an image...
I fixed the link now...
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Old 02-22-2019, 10:31 PM   #6
berthfield
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Default Re: Help identifying power ic?

Quote:
Originally Posted by PeteS in CA View Post
Either img tags are not working, or vBulletin is not recognizing the imgur page as an image, https://imgur.com/a/2oQ3LXE .

I can't see clearly any IC such as berthfield described, but there is an electrolytic cap in the pic that clearly is swollen and vented.
I changed that cap after taking the picture. The IC turned out to be a LDO as suggested but after searching for a few hours I was unable to find any replacements locally. The only markings on it were DDAAC not sure what that was supposed to signify.

Edit: Forgot to mention that in the interest of time I removed the offending component and just went with a 7805 mounted to the side for 5v supply. There aren't many SMD suppliers locally and I was not willing to wait.

Thanks all for your help.

Last edited by berthfield; 02-22-2019 at 10:34 PM..
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