DC/DC Converters Target Portable Apps

Four high-efficiency, synchronous step-down dc/dc converters have been optimized for portable applications powered by one lithium-ion cell or three NiCd, NiMH or alkaline cells. The NCP1508, NCP1509, NCP1510A and NCP1511 are current-mode devices that employ synchronous rectification, which is said to promote high efficiency, better line regulation, easy compensation and reduced parts count. Each device features a built-in PWM oscillator, integrated soft-start, cycle-by-cycle current limiting and thermal protection. The various devices have slightly different choices of digitally-programmable output voltages. The NCP1510A and NCP1511 are available in Micro Bump, while the NCP1509 and NCP1508 are available in 3 mm x 3 mm DFN packages. All are available in lead-free versions. The devices are priced between $0.53 and $0.56 each/10,000. ON SEMICONDUCTOR, Phoenix, AZ. (800) 282-9855.