LTC1174

U U FEATURES ■ High Efficiency: Up to 94% ■ Peak Inductor Current Independent of Inductor Value ■ Short-Circuit Protection ■ Optimized for 5V to – 5V Applications ■ Wide VIN Range: 4V to 18.5V ■ Low Dropout Operation ■ Low-Battery Detector ■ Pin Selectable Current Limit ■ Internal 0.9Ω Power Switch: VIN = 9V ■ Only Four External Components Required ■ 130µA Standby Current ■ Active Low Micropower Shutdown U APPLICATIO S ■ Distributed Power Systems ■ Step-Down Converters ■ Inverting Converters ■ Memory Backup Supply ■ Portable Instruments ■ Battery-Powered Equipment LTC1174 LTC1174-3.3/LTC1174-5 High Efficiency Step-Down and Inverting DC/DC Converter DESCRIPTIO The LTC®1174 is a simple current mode DC/DC converter ideally suited for 9V to 5V, 5V to 3.3V or 5V to – 5V operation. With an internal 0.9Ω switch (at a supply voltage of 9V), the LTC1174 requires only four external components to construct a complete high efficiency DC/DC converter. Under a no load condition the LTC1174 draws only 130µA. In shutdown, it draws a mere 1µA making this converter ideal for current sensitive applications. In dropout, the internal P-channel MOSFET switch is turned on continuously allowing the user to maximize the life of the battery source. The maximum inductor current of the LTC1174 family is pin selectable to either 340mA or 600mA, optimizing efficiency for a wide range of applications. Operation up to 200kHz permits the use of small surface mount inductors and capacitors. For applications...