General Description

The Micrel MIC2285A is a high efficiency 8MHz PWM synchronous buck (step-down) regulator that features a LOWQ® LDO standby mode that draws only 20µA of quiescent current. The MIC2285A allows an ultra-low noise, small size, and high efficiency solution for portable power applications.

Features

• 2.7 to 5.5V supply/input voltage

• Light load LOWQ® LDO mode

– 20µA quiescent current

– Low noise, 75µVrms

• 8MHz PWM mode

– Output current to 600mA

– >90 efficiency

– 100 maximum duty cycle

• Adjustable output voltage option down to 1V

– Fixed output voltage options available

• Ultra-fast transient response

• Requires only a 0.47µH inductor

• Enables sub 0.55mm profile solution

• Fully integrated MOSFET switches

• Micropower shutdown

• Thermal shutdown and current limit protection

• 10-pin 2mm x 2mm x 0.55mm MLF® package

• –40°C to +125°C junction temperature range

Applications

• Cellular phones

• PDAs

• USB peripherals