General Description

The ML4854 is a low power boost regulator designed for low voltage DC to DC conversion in two-cell battery powered systems such as cell phones and PDAs. The converter starts up at 1.3V and has an operating input voltage range from 1.6V to 4.5V. After the start it operates at an input voltage as low as 0.8V. Output voltage can be adjusted by external resistors from 3.3V to 5V with a maximum load current of 0.5A.

Features

• 95 Efficiency at 200mA Load Current

• Integrated Peak Current Limit

• Variable Output Voltage Determined by External Resistors

• Variable On-time Pulse Frequency Modulation (PFM)

• Fully Internal Synchronous Rectifier (no external diodes) for High Efficiency and Low Peak Currents

• Low-Battery Detection

• Logic Controlled Shutdown with True Load Disconnect

Applications

• 2-3 alkaline/NiMH cells or 1 Li-Ion cell Operated Devices

• Cell Phones

• Medical Devices

• PDAs

• Portable Instrumentation