The LTC1474/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.The low supply current coupled with Burst Mode™operation enables the LTC1474/LTC1475 to maintain high efficiency over a wide range of loads. These features, along with their capability of 100% duty cycle for low dropout and wide input supply range, make the LTC1474/LTC1475 ideal for moderate current (up to 300mA) battery-powered applications.The peak switch current is user-programmable with an optional sense resistor (defaults to 325mA minimum if not used) providing a simple means for optimizing the design for lower current applications. The peak current control also provides short-circuit protection and excellent start-up behavior. A low-battery detector that remains functional in shutdown is provided.The LTC1474/LTC1475 series availability in 8-lead MSOP and SO packages and need for few additional components provide for a minimum area solution.ApplicationsCellular Telephones and Wireless Modems4mA to 20mA Current Loop Step-Down ConverterPortable InstrumentsBattery-Operated Digital DevicesBattery ChargersInverting ConvertersIntrinsic Safety Applications