DESCRIPTION

The LX2172/73 are fixed-frequency, current-mode switching regulator integrated circuits. These ICs contain all necessary control circuitry plus a 1.25A on-board transistor to design a complete DC:DC switching regulator with minimum external components.

All functions are integrated into a single IC, available in 8-pin DIP and SOIC or a 5- pin TO-220 power package, making them extremely easy to design with and use. The LX2172/73 are optimized for boost and flyback applications, but can also be used in forward and inverting converter configuations.

KEY FEATURES

■ 1.25A, 65V Internal Power Switch

■ 3V - 25V Input Voltage Range

■ Current-Mode Operation

■ Improved Internal Cycle-ByCycle Current Limiting

■ Thermal Shutdown

■ Less Than 10µA Quiescent Current In Microprocessor Shutdown Mode

■ External Frequency Synchronization Possible

■ 100kHz Operating Frequency IGNS

APPLICATIONS

■ Boost Converter

■ Laptop / Notebook Computers

■ Portable Equipment

■ Small Motor Applications

■ Flyback Converters