Kobo Aura H2O burned charging circuit component identification

Thread Starter

TheRealShadowHunter

Joined Jul 6, 2021
3
Hello AAC-members,

First time poster, long time electronics hobbyist.

My Kobo Aura H2O ebook didn't charge anymore (battery was immediately reaching 100% when inserting charger) and I found a burned, what I believe to be, voltage regulator. I would like to replace it but cannot quite figure out maker and specs. Battery was already replaced.

Does anyone recognized this SOT-23 part or have Kobo schematics?

kobo_forum.jpg
The PCB silkscreen menitions "U3" and the component imprint reads U?5GA where I suspect ? to be either "Y" or "P". Please feel free to have a look at the attached picture. There is also a similar component close to it reading UP5GB (so might the same)

I hope someone can support, it would be a shame to dispose of a perfectly working ebook for a 10 cents component. Issue was caused by faulty wall charger that also blew up my Galaxy S10.

Thank you so much.

With best regards,

TheRealShadowHunter
 

Thread Starter

TheRealShadowHunter

Joined Jul 6, 2021
3
Hi ericgibbs,

Thank you for your feedback.

I appreciatie your effort of inverting the image to make the imprint more readable.

Could also be "UY5GA" but alas none of them yield any usable result in Google...

I searched for makers with "UY" but also no result...

Thank you.

TheRealShadowHunter
 

Irving

Joined Jan 30, 2016
3,845
Its not so simple, SMD part marking is a minefield even when youre 100% sure of the mark. I'd usually look at the board to trace where the pins connect to, to get an idea of what the part is meant to do. Its probably a voltage regulator...

The most likely part match so far is:
1626204072433.png

The reason I'm a little unsure is that 4v would be unusual... Also that case isn't an SOT-89, more likely a SOT23-5, but the UY is compelling for that part #.

It could be a FremontMicro FT533Ga 2.8v regulator, but that's even less likely..

More research needed...
 

sagor

Joined Mar 10, 2019
903
Is the battery actually any good? When a bunch of cells (multi-cell battery) shoot up to full voltage, that means the cells are not taking current and indicates one of the cells is open and conduction is only happening via some electrolyte. Voltage potential is there, but no real current flow.
If the charger was bad, it woul not cause the battery to indicate 100% when plugged in.
 

Irving

Joined Jan 30, 2016
3,845
Well if that's part of the charging circuit then maybe 4v is the right value.... I'm just not yet 100% convinced its the right part...
 
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