General Description

50 mA boost converter using Pulse Frequency Modulation, or PFM, technique, in 5-lead SOT-89 or a 5-lead SOT-23 package. Only 3 external components are needed to complete the switcher design.

Features

• 85 conversion efficiency at 50mA out

• Start-up voltages as low as 900mV

• ±2.5 accurate outputs

• Complete switch design with only 3 external components

• Automatically senses load variations to select the optimal duty cycle and extend conversion efficiencyover a wide range

• External transistor configuration to run as switcher controller

• Shutdown to 0.5µA

Applications

• Cellular phones, pagers

• Cameras, video recorders

• Palmtops and PDAs