San Jose, Calif. Micrel Inc. has launched the MIC2238, a 2.5-MHz dual 800 mA synchronous buck (step-down) regulator housed in a 3 x 3-mm MLF package. The device provides two out-of-phase outputs of up to 800 mA each and offers light load efficiencies of up to 94 percent at 5 mA and peak efficiencies of more than 96 percent.
The MIC2238's unique switching architecture scheme, called Trickle Mode, enables light load efficiency for Li-ion battery-powered systems. The MIC2238 is suitable for portable applications including cellular phones, portable media players, WiMax modules, GPS systems, digital still cameras and video cameras.
The MIC2238 device offers an input voltage range from 2.5 to 5.5 V and an ultra-low quiescent current of 28 uA at light loads. This ensures that only a trickle of current is drawn from the battery, which extends standby time. The device's design offers two modes of operation, a variable frequency Trickle Mode operation for highest light load efficiency with an automatic switchover into full load, and an option for running the device at a constant frequency. In addition, the device offers a power good output signal for sequencing capability.
Micrel, Inc. , www.micrel.com