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?


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

 

Really no one recognizes this wee part :-(

 

hi,
May help , it is coded UY56A

E

 

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

 

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:


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...

 

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.

 

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...

 

Another victim of the same fault in the same device here.

This seems to be the only page on the internet where this component is discussed, so I'd like to contribute with my findings in case it's useful for somebody else.

In my device, pin 3 of the unknown component is connected to ground, while 1 is connected to R12 and 2, 4 and 5 are connected to test point 1, but this could be due to the device burning and shorting of course.
In case of the similarly packaged and named component next to it, it has the same pin number 3 connected to ground.

In any case, pin 3 being ground seems to be incompatible with the possibility of UM154xx (UM153 is already impossible due to it being a different package), as it's an active high EN pin.

As for the FT533Ga series, it fcould be compatible with the SOT-23-5C/SC-70C pinout, but that would mean it's an FT533Xf.

Search in alldatasheet for *UY5* only returned LEDs, TO-3 transistors, displays, oscillators, capacitors and a couple MOSFETS with incompatible package and power.

I also triaed to search for information about the main IC around there which seems to be the 16pin one marked as 8ZF. No information about it.

I wish I cuyld fix this device.
I tried hooking it up to a wireless charge coil and circuit, so I have an alternative powering system, but it fails upon reassembly due to the lack of space without metal interference.

 

Another victim of the same fault in the same device here.

This seems to be the only page on the internet where this component is discussed, so I'd like to contribute with my findings in case it's useful for somebody else.

In my device, pin 3 of the unknown component is connected to ground, while 1 is connected to R12 and 2, 4 and 5 are connected to test point 1, but this could be due to the device burning and shorting of course.
In case of the similarly packaged and named component next to it, it has the same pin number 3 connected to ground.

In any case, pin 3 being ground seems to be incompatible with the possibility of UM154xx (UM153 is already impossible due to it being a different package), as it's an active high EN pin.

As for the FT533Ga series, it fcould be compatible with the SOT-23-5C/SC-70C pinout, but that would mean it's an FT533Xf.

Search in alldatasheet for *UY5* only returned LEDs, TO-3 transistors, displays, oscillators, capacitors and a couple MOSFETS with incompatible package and power.

I also triaed to search for information about the main IC around there which seems to be the 16pin one marked as 8ZF. No information about it.

I wish I cuyld fix this device.
I tried hooking it up to a wireless charge coil and circuit, so I have an alternative powering system, but it fails upon reassembly due to the lack of space without metal interference.

Another victim of the same fault in the same device here.

This seems to be the only page on the internet where this component is discussed, so I'd like to contribute with my findings in case it's useful for somebody else.

In my device, pin 3 of the unknown component is connected to ground, while 1 is connected to R12 and 2, 4 and 5 are connected to test point 1, but this could be due to the device burning and shorting of course.
In case of the similarly packaged and named component next to it, it has the same pin number 3 connected to ground.

In any case, pin 3 being ground seems to be incompatible with the possibility of UM154xx (UM153 is already impossible due to it being a different package), as it's an active high EN pin.

As for the FT533Ga series, it fcould be compatible with the SOT-23-5C/SC-70C pinout, but that would mean it's an FT533Xf.

Search in alldatasheet for *UY5* only returned LEDs, TO-3 transistors, displays, oscillators, capacitors and a couple MOSFETS with incompatible package and power.

I also triaed to search for information about the main IC around there which seems to be the 16pin one marked as 8ZF. No information about it.

I wish I cuyld fix this device.
I tried hooking it up to a wireless charge coil and circuit, so I have an alternative powering system, but it fails upon reassembly due to the lack of space without metal interference.

The same fault, the same device
I removed this IC, then it charges well