The LTC1874 is a dual constant frequency current mode step-down DC/DC controller with excellent AC and DC load and line regulation. Each controller has an accurate undervoltage lockout that shuts down the individual controller when the input voltage falls below 2.0V.The LTC1874 boasts ±2.5% output voltage accuracy and consumes only 270µA of quiescent current per controller. The LTC1874 is configured with Burst Mode operation, which enhances efficiency at low output current for applications where efficiency is a prime consideration.To further maximize the life of a battery source, each external P-channel MOSFET is turned on continuously in dropout (100% duty cycle). In shutdown, each controller draws a mere 8µA. High constant operating frequency of 550kHz allows the use of small external inductors.The LTC1874 is available in a small footprint 16-lead narrow SSOP.Applications1- or 2-Cell Lithium-Ion-Powered ApplicationsDistributed 3.3V, 2.5V or 1.8V Power SystemsPersonal Information AppliancesPortable Computers