This part is a kind of semiconductor called RT9045.

Function of this product has 1.8A Sink/Source Bus Termination Regulator.

Manufacturers : Richtek

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RT9045 Cost-Effective, 1.8A Sink/Source Bus Termination Regulator General Description The RT9045 is a simple, cost-effective and high-speed linear regulator designed to generate termination voltage in Double Data Rate (DDR) memory system to comply with the devices requirements. The regulator is capable of actively sinking or sourcing up to 1.8A while regulating an output voltage to within 20mV. The output termination voltage can be tightly regulated to track VDDQ / 2 by two external voltage divider resistors or the desired output voltage can be programmed by externally forcing the REFEN pin voltage. The RT9045 also incorporates a high-speed differential amplifier to provide ultra-fast response in line/load transient. Other features include extremely low initial offset voltage, excellent lo [ ... ]

RT9045 PDF Datasheet Download