SMD finding replacements

I am hoping for some help on finding what exactly these 2 chips are so they can be replaced. The numbers listed on them are 3311 and W with a line under it and NA7 after. I have tried to find them but so far no luck. They are in a LED power distribution board. Any help would be appreciated.

I’m guessing the 3311 is really 331x where the x is a date code. That would make it a FDC6331L. This page has an image of one:


Thanks Scorch I will try that…any guess at the 2nd one? I can find nothing that even resembles the w with an underscore or NA7

There is a good resource here:

The W plus underbar is possibly a makers logo? Although it’s not in the table there…

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Check this sight out for SMD identification (it is the has the most codes I have seen in one place):

There are other options there for the “331” code.

I don’t see anything for the other component.

@Josephsmuse why do you think you need to replace these components?

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You most likely cant see it in the photos but th NA7 is cracked at the 7 and the 3311 shows shorted on several pins

Context is also important here; what part of the circuit do they come from? Power supply, output, video/audio etc, so manyidentical markings get used that this helps narrow down the search.

Note that the 7 is printed differently! I think this means you need to treat this as a year/batch number, not part of the identification number.

If you look for just 'NA' as the prefix on the site (great URL!, cheezy but made me laugh) there are a load of 6pin Power chips in the list. Narrowing down from there is harder, and where having a basic understanding of what sort of chip you have, and how it is connected in-circuit becomes useful.

On this topic; have you attempted to find a schematic for the PCB? Using the PCB markings sometimes comes up trumps; and a proper schematic will probably list the full part number.

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Owen…no schematic is available for it, the manufacturer won’t even sell a part (that’s why I need to fix the board) testing the board with the chip out, Pin 1 shows nothing just using a DVM pin 2 next to pin 1 shows 5.2v, pin 3 shows 5.2v, pin 4 across from 3 shows 5.2v pin 5 tests as ground and pin 6 tests as ground. It is listed on the board as U13, and the board is driving a 4.3" lcd monitor.