The MAX1717 step-down controller is intended for core CPU DC-DC converters in notebook computers. It features a dynamically adjustable output, ultra-fast transient response, high DC accuracy, and high efficiency needed for leading-edge CPU core power supplies. Maxim's proprietary Quick-PWMTM quick-response, constant-on-time PWM control scheme handles wide input/output voltage ratios with ease and provides 100ns "instant-on" response to load transients while maintaining a relatively constant switching frequency. The output voltage can be dynamically adjusted through the 5-bit digital-to-analog converter (DAC) inputs over a 0.925V to 2V range. A unique feature of the MAX1717 is an internal multiplexer (mux) that accepts two 5-bit DAC settings with only five digital input pins. Output voltage transitions are accomplished with a proprietary precision slew-rate control that minimizes surge currents to and from the battery while guaranteeing "just-in-time" arrival at the new DAC setting. High DC precision is enhanced by a two-wire remotesensing scheme that compensates for voltage drops in the ground bus and output voltage rail. Alternatively, the remote-sensing inputs can be used together with the MAX1717's high DC accuracy to implement a voltage-positioned circuit that modifies the load-transient response to reduce output capacitor requirements and full-load power dissipation.