The LTC1753 is a high power, high efficiency switching regulator controller optimized for 5V input to a digitally programmable 1.3V-3.5V output. The internal 5-bit DAC programs the output voltage from 1.3V to 2.05V in 50mV increments and from 2.1V to 3.5V in 100mV increments. The precision internal reference and an internal feedback system provide an output accuracy of 1.5% at room temperature and typically 2% over temperature, load current and line voltage shifts. The LTC1753 uses a synchronous switching architecture with two external N-channel output devices, providing high efficiency and eliminating the need for a high power, high cost P-channel device. Additionally, it senses the output current across the on-resistance of the upper Nchannel FET, providing an adjustable current limit without an external low value sense resistor.