CN 2001YS4

Could somebody help me to fetch more details about this IC?

You might do better if you give more details, although it's quite likely it's an in-house number so completely meaningless.

IC's use "markings" now that make it quite difficult. markings are re-used too., so the package matters. M1 on a diode package may mean something way diffierent if found on a 16 pin IC. The designation on the PCB helps like U2.

It's more "detective work" than it used to be.