Identifying QFN16 3x3 mm buck DC-DC Li-ion charger

[martonmiklos]

Hi folks,

I am trying to repair a Braun Silk Epil 9 series motherboard.
The on board single cell Li-ion DCDC charger IC looks to be defective.
It runs from 12V, and when it starts charging it brings my bench PSU CC.
I have drawn a reverse engineered symbol for it, does anyone could identify it?
I used up all my google fu with qfn16 li ion and dcdc keywords, but I have not found any pinout compatible one.
The markings on the IC:
4561
1909
32144

[fzabkar]

Perhaps if we could identify the other ICs, this may help us to determine the manufacturer, or at least the country of manufacture.

BTW, the second line appears to be a YYWW (year/week) date code. I have confirmed this by examining other PCBs.

[thm_w]

Does the output go directly to a single lithium cell? Or does it pass via another IC.
If there is space bodge in a TP5100 or similar charging module. Or convert to USB and use TP4056.

[martonmiklos]

There are not much identifiable parts on the board other than the MCU (made by Cypress).
There are two BC847BS on the board the rest of the IC-s/transistors are not identifiable. 

[martonmiklos]

The output is connected to the li-ion cell through a fuse.

There are some status reporting wired to the MCU which needs to be reverse engineered.
Before the IC removal the device indicated charging (with a LED blink code) without charger connected (the device cannot be operated during charging). When I shorted out the charging input pins it got functional. After the IC removal I cannot turn it on.

[fzabkar]

Try asking at ...

https://www.badcaps.net/forum/forumdisplay.php?f=29