DESCRIPTION
The LTC®3776 is a 2-phase dual output synchronous stepdown switching regulator controller for DDR/QDR memory termination applications. The second controller regulates its output voltage to 1/2 VREF while providing symmetrical source and sink output current capability.

FEATURES
■ No Current Sense Resistors Required
■ Out-of-Phase Controllers Reduce Required
   Input Capacitance
■ VOUT2 Tracks 1/2 VREF
■ Symmetrical Source/Sink Output Current
   Capability (VOUT2)
■ Spread Spectrum Operation (When Enabled)
■ Wide VIN Range: 2.75V to 9.8V
■ Constant Frequency Current Mode Operation
■ 0.6V ±1.5% Voltage Reference (VOUT1)
■ Low Dropout Operation: 100% Duty Cycle
■ True PLL for Frequency Locking or Adjustment
■ Internal Soft-Start Circuitry
■ Power Good Output Voltage Monitor
■ Output Overvoltage Protection
■ Micropower Shutdown: IQ = 9µA
■ Tiny Low Profile (4mm × 4mm) QFN and Narrow
   SSOP Packages

APPLICATIONS
■ DDR, DDR II and QDR Memory
■ SSTL, HSTL Termination Supplies
■ Servers, RAID Systems
■ Distributed DC Power Systems