LTC1553L

The LTC^®1553L is a high power, high efficiency switchingregulator controller optimized for a 5V input to 1.8V-3.5Voutput applications. It features a digitally programmableoutput voltage, a precision internal reference and an internalfeedback system that provides output accuracy of ±1.5% atroom temperatureand typically ±2% over-temperature, loadcurrent and line voltage shifts. The LTC1553L uses a syn-chronous switching architecture with two external N-channeloutput devices, providing high efficiency and eliminating theneed for a high power, high cost P-channel device. Addition-ally, it senses the output current across the on-resistance ofthe upper N-channel FET, providing an adjustable currentlimit without an external low value sense resistor.

The LTC1553L free-runs at 300kHz and can be synchronizedto a faster external clock if desired. It includes all the inputsand outputs required to implement a power supply conform-ing to the  Intel Pentium® II Processor VRM 8.2 DC/DCConverter Specification.