DESCRIPTION
The LTC®3546 is a dual, constant-frequency, synchronous step down DC/DC converter for medium power applications. The design consists of 2A and 1A primary output switches. In addition to the 2A/1A capability, a 1A dependant output switch can be externally connected to either of the primary outputs to produce 3A/1A dual regulator or 2A/2A dual regulator confi gurations.

FEATURES
■ VIN Range: 2.25V to 5.5V
■ VOUT Range: 0.6V to 5V
■ Programmable Frequency Operation; 2.25MHz, or
   Adjustable Between 0.75MHz to 4MHz
■ Low RDS(ON) Internal Switches
■ High Effi ciency: Up to 96%
■ No Schottky Diodes Required
■ Short-Circuit Protected
■ Current Mode Operation for Excellent Line and Load
   Transient Response
■ Low Ripple Burst Mode Operation (30mVP-P),
   IQ = 160μA
■ Ultralow Shutdown Current: IQ < 1μA
■ Low Dropout Operation: 100% Duty Cycle
■ Power Good Output For Each Channel
■ Externally or Internally Programmable Burst Level
■ External or Internal Soft-Start or Supply Tracking
■ Available in Thermally Enhanced 28-Lead
   (4mm × 5mm) QFN and TSSOP Packages

APPLICATIONS
■ Netbooks/Ultra-Mobile PCs
■ PC Cards
■ Wireless and DSL Modems
■ Point of Load DC/DC Conversion