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