The LTC3618 is a dual synchronous step-down regulator using a current mode, constant-frequency architecture. It provides a complete DDR solution with an input voltage range from 2.25V to 5.5V.The output of the first step-down regulator offers a high accuracy VDDQsupply. A buffered reference generates VTTR at 50% of VDDQIN and drives loads up to ±10mA. The second regulator generates the DDR termination voltage (VTT) equal to VTTR. Both regulators are capable of delivering ±3A of load current at 1MHz switching frequency.The operating frequency is externally programmable up to 4MHz, allowing the use of small surface mount inductors. 0°, 90°, or 180° of phase shift between the two channels can be selected to minimize input current ripple. For switching noise-sensitive applications, the LTC3618 can be synchronized to an external clock up to 4MHz.The LTC3618 is offered in leadless 24-pin 4mm × 4mm QFN and thermally enhanced 24-pin TSSOP packages.APPLICATIONSDDR MemorySupports DDR, DDR2, and DDR3 StandardsTracking Supplies