DESCRIPTION
The LTC®3719 is a 2-phase, VID programmable, synchronous step-down switching regulator controller that drives two N-channel external power MOSFET stages in a fixed frequency architecture. The 2-phase controller drives its two output stages out of phase at frequencies up to 300kHz to minimize the RMS ripple currents in both input and output capacitors. The 2-phase technique effectively multiplies the fundamental frequency by two, improving transient response while operating each channel at an optimum frequency for efficiency. Thermal design is also simplified.

FEATURES
■ Output Stages Operate Antiphase Reducing Input
   and Output Capacitance Requirements and Power
   Supply Induced Noise
■ Dual Input Supply Capability for Load Sharing
■ 5-Bit AMD CPU VID Code:
   VOUT = 0.8V to 1.55V
■ ±1% Output Voltage Accuracy
■ True Remote Sensing Differential Amplifier
■ Power Good Output Voltage Monitor
■ Supports Active Voltage Positioning
■ Current Mode Control Ensures Current Sharing
■ OPTI-LOOP® Compensation Minimizes COUT
■ Three Operational Modes: PWM, Burst and Cycle Skip
■ Programmable Fixed Frequency: 150kHz to 300kHz
■ Wide VIN Range: 4V to 36V Operation
■ Adjustable Soft-Start Current Ramping
■ Internal Current Foldback and Short-Circuit Shutdown
■ Overvoltage Soft Latch Eliminates Nuisance Trips
■ Available in 36-Lead Narrow (0.209) SSOP Package

APPLICATIONS
■ Servers and Workstations