DESCRIPTION
The LX1681/1682 are monolithic, pulsewidth modulator controller ICs. They are designed to implement a flexible, low cost buck (step-down) regulator supply with minimal external components.
The LX1681 is a non-synchronous controller; the LX1682 has a synchronous driver for higher efficiency.

KEY FEATURES
■ Fixed 200kHz Switching Frequency
■ Constant Frequency Voltage-Mode Control Requires NO External Compensation
■ Hiccup-Mode Over-Current Protection
■ High Efficiency
■ Output Voltage Set By Resistor Divider
■ Under-Voltage Lockout
■ Soft-Start And Enable
■ Synchronous Rectification (LX1682)
■ Non-Synchronous Rectification (LX1681)
■ Small, 8-pin Surface Mount Package

APPLICATIONS
■ 5V to 3.3V Or Less Buck Regulators
■ FPGA Supplies
■ Microprocessor Chipset Supplies (e.g. Camino, Whitney, etc.)
■ Rambus® RIMMTM Supplies
■ Hard Disk Drives
■ Computer Add-on Cards