DESCRIPTION
The LX1681/1682 are monolithic, pulse-width 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.
The output voltage is adjustable by means of a resistor divider to set the voltage between 1.25V and 4.5V.

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© RIMM™ Supplies
◾ Hard Disk Drives
◾ Computer Add-on Cards