This part is a kind of semiconductor called AP2301.

Function of this product has 1.5A DDR TERMINATION REGULATOR.

Manufacturers : BCD Semiconductor

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Preliminary Datasheet 1.5A DDR TERMINATION REGULATOR General Description The AP2301 linear regulator is designed to meet the JEDEC specification SSTL-2 and SSTL-18 for termination of DDR-SDRAM. The regulator can sink or source up to 1.5A current continuously, offers enough current for most DDR applications. Output voltage is designed to track the reference voltage within a 2% tolerance for load regulation while preventing shooting through on the output stage. On-chip thermal limiting provides protection against a combination of high current and ambient temperature which would create an excessive junction temperature. The AP2301, used in conjunction with series termination resistors, provides an excellent voltage source for active termination schemes of high speed transmission lines as thos [ ... ]

AP2301 PDF Datasheet Download