I think you are right. Because I never came across such a strange marking on ICs before.That is most likely an internal factory number. Remember they do not want you to repair them but to buy new ones. There are a number of videos on youtube in regard to chargers. Search on " Black&Decker 18V Li-ion charger "
for example: https://www.youtube.com/watch?v=c-pTziUV1as
Thanks for this one.well..actually..i was told that it is a richtek R7731A.
i was directed to these sites.... http://www.smdmark.com/en-US/search/code?id=dp%3D geometry dash online and https://www.s-manuals.com/smd
From their datasheet the marking is really idp=W where W is a date code.
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