This part is a kind of semiconductor called APW8819.

Function of this product has DDR TOTAL POWER SOLUTION SYNCHRONOUS BUCK CONTROLLER.

Manufacturers : ANPEC

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APW8819 DDR TOTAL POWER SOLUTION SYNCHRONOUS BUCK CONTROLLER WITH 1.5A LDO Features Buck Controller (VDDQ) General Description The APW8819 integrates a synchronous buck PWM controller to generate VDDQ, a sourcing and sinking LDO linear regulator to generate VTT. It provides a complete power supply for DDR2 and DDR3 memory system. It offers the lowest total solution cost in system where space is at a premium. The APW8819 provides excellent transient response and accurate DC voltage output in PFM Mode. In Pulse Frequency Mode (PFM), the APW8819 provides very high efficiency over light to heavy loads with loading-modulated switching frequencies. The APW8819 is equipped with accurate current-limit, output under-voltage, and output over-voltage protections. A Power-On- Reset function monitors [ ... ]

APW8819 PDF Datasheet Download