General Description
The AP1603 is a high efficiency step-up DC/DC converter for applications using as few as a single NiMH or Li-Ion battery cells. Only four external components are required to deliver a fixed output voltage of 3.3V. The AP1603 starts up from less than 0.9V input with 1mA load. Pulse Frequency Modulation scheme brings optimized performance for applications with light output loading and low input voltages. The output ripple and noise are lower compared with the circuits operating in PSM mode.

Features
• A Guaranteed Start-Up from less than 0.9 V
• High Efficiency
• Low Quiescent Current
• Less Number of External Components needed
• Low Ripple and Low Noise
• Space Saving Lead-Free Packages: SOT26
• Lead Free Finish/RoHS Compliant for Lead Free products (Note 1)

Applications
• Pagers
• Cameras
• Wireless Microphones
• Pocket Organizers
• Battery Backup Suppliers
• Portable Instruments