Electronics > Beginners

Fake Alpha and Omega semi parts?

(1/2) > >>

umkumiut:
Hi All,

I bought two Li-Ion protection modules from ebay and the main MOSFETs look suspicious to me on one of them.
Both are for 2 cells in series and have balance circuits too.

The first one looks decent to me (blue soldermask). It is rated for 10A, uses 2x2 MOSFETs to switch the load with the marking "D514" and the logo of Alpha and Omega semi.

1st module:
https://imgur.com/a/rzAXm9C

The second has the suspicious looking parts (green soldermask). The module itself should handle 20A. The main switching MOSFETs have the logo of the AOS again, with the marking "D472". However, it looks like that the original markings have been grinded off and then they were marked by laser again. Compared with the MOSFETs of the other board, the texture of the molding is pretty different.

2nd module:
https://imgur.com/a/i15hoU9
https://imgur.com/a/keVY0GF
https://imgur.com/a/scsFg3g

What do you think? Does it really worth faking an AOS part?
Would you trust it?

mvs:

--- Quote from: umkumiut on February 04, 2019, 05:26:57 pm ---What do you think? Does it really worth faking an AOS part?
Would you trust it?

--- End quote ---
Why not? Its a popular brand in Asia. You can measure RDSon and take decision based on numbers (Vds can not be an issue here), or just replace it with proper MOSFET you can trust.

BTW AOD472 is obsolete, a bit strange decision to use it in production and/or to fake it.

Tomorokoshi:
Likely fake. Sanded and lasered. Notice the rough edges along the perimeter of the top surface.

As for:

--- Quote from: mvs on February 04, 2019, 05:52:17 pm ---BTW AOD472 is obsolete, a bit strange decision to use it in production and/or to fake it.

--- End quote ---

Obsolete parts almost appear to be targeted for this type of fake. It makes the supplier of the fake become very attractive to the company purchasing a part they otherwise can't get.

wraper:
100% sanded.

mvs:

--- Quote from: Tomorokoshi on February 04, 2019, 06:03:13 pm ---Obsolete parts almost appear to be targeted for this type of fake. It makes the supplier of the fake become very attractive to the company purchasing a part they otherwise can't get.

--- End quote ---
Yes, in case of some custom/special parts it make sense. But MOSFET are quite generic parts, there is almost no effort to pickup replacement.

Navigation

[0] Message Index

[#] Next page

There was an error while thanking
Thanking...
Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod