
Linear Technology
DESCRIPTIONU
The LTC®1474/LTC1475 series are high efficiency step down converters with internal P-channel MOSFET power switches that draw only 10µA typical DC supply current at no load while maintaining output voltage. The LTC1474 uses logic-controlled shutdown while the LTC1475 features pushbutton on/off.
FEATURES
■ High Efficiency: Over 92% Possible
■ Very Low Standby Current: 10µA Typ
■ Available in Space Saving 8-Lead MSOP Package
■ Internal 1.4Ω Power Switch (VIN = 10V)
■ Wide VIN Range: 3V to 18V Operation
■ Very Low Dropout Operation: 100% Duty Cycle
■ Low-Battery Detector Functional During Shutdown
■ Programmable Current Limit with Optional
Current Sense Resistor (10mA to 400mA Typ)
■ Short-Circuit Protection
■ Few External Components Required
■ Active Low Micropower Shutdown: IQ = 6µA Typ
■ Pushbutton On/Off (LTC1475 Only)
■ 3.3V, 5V and Adjustable Output Versions
APPLICATIONS
■ Cellular Telephones and Wireless Modems
■ 4mA to 20mA Current Loop Step-Down Converter
■ Portable Instruments
■ Battery-Operated Digital Devices
■ Battery Chargers
■ Inverting Converters
■ Intrinsic Safety Applications