LTC1266

U U LTC1266 LTC1266-3.3/LTC1266-5 Synchronous Regulator Controller for N- or P-Channel MOSFETs FEATURES DESCRIPTIO s Ultrahigh Efficiency: Over 95% Possible s Drives N-Channel MOSFET for High Current or P-Channel MOSFET for Low Dropout s Pin Selectable Burst Mode Operation s 1% Output Accuracy (LTC1266A) s Pin Selectable Phase of Topside Driver for Boost or Step-Down Operation s Wide VIN Range: 3.5V to 20V s On-Chip Low-Battery Detector s High Efficiency Maintained Over Large Current Range s Low 170µA Standby Current at Light Loads s Current Mode Operation for Excellent Line and Load Transient Response s Logic Controlled Micropower Shutdown: IQ < 40µA s Short-Circuit Protection s Synchronous Switching with Nonoverlaping Gate Drives s Available in 16-Pin Narrow SO Package U APPLICATIO S s Notebook and Palmtop Computers s Portable Instruments s Cellular Telephones s DC Power Distribution Systems s GPS Systems The LTC®1266 series is a family of synchronous switching regulator controllers featuring automatic Burst ModeTM operation to maintain high efficiencies at low output currents. These devices drive external power MOSFETs at switching frequencies up to 400kHz using a constant offtime current mode architecture providing constant ripple current in the inductor. They can drive either an N-channel or a P-channel topside MOSFET. The operating current level is user-programmable via an external current sense resistor. Wide input supply range allows operation from 3.5V to 18V (2...