DESCRIPTION

· The MCP1603/B/L is a high-efficiency, 500 mA synchronous buck regulator with a 2.7V to 5.5V input range, suitable for 1-cell Li-Ion or 2-cell/3-cell NiMH/NiCd battery applications.

· It operates in 2.0 MHz fixed-frequency PWM mode for low noise and ripple at heavy loads, and automatically switches to PFM mode at light loads for minimal current draw.

· The MCP1603B operates exclusively in PWM mode, ideal for applications sensitive to PFM-induced ripple.

· Available in adjustable or fixed output voltages, requiring minimal external components for a compact solution.

· Includes UVLO, overtemperature, and overcurrent protection.

FEATURES

· Over 90% typical efficiency.

· Output current up to 500 mA.

· Low PFM quiescent current: 45 µA (MCP1603/L).

· Low shutdown current: 0.1 µA.

· Adjustable output voltage: 0.8V to 4.5V.

· Fixed output voltages: 1.2V, 1.5V, 1.8V, 2.5V, 3.3V (MCP1603/L); 1.8V, 3.3V (MCP1603B).

· 2.0 MHz fixed-frequency PWM.

· Automatic PWM-to-PFM transition (MCP1603/L).

· PWM mode only (MCP1603B).

· 100% duty cycle operation.

· Internally compensated.

· Space-saving packages: 5-Lead TSOT, 8-Lead 2x3 DFN.

APPLICATIONS

· Cellular telephones.

· Portable computers.

· Organizers/PDAs.

· USB-powered devices.

· Digital cameras.

· Portable equipment.

· +5V or +3.3V distributed systems.

· Headsets.