MAX15026/MAX15026BETD DC-DC Synchronous Buck Controller The MAX15026 synchronous step-down controller operates from a 4.5V to 28V input voltage range and produces an adjustable output voltage from 85% of the input voltage down to 0.6V while supporting loads up to 25A. The device allows monotonic start-up to the pre-bias bus without discharging the output, and features an adaptive internal digital soft-start feature. The MAX15026 can adjust the switching frequency from 200kHz to 2MHz with an external resistor. The adaptive synchronous rectification of the MAX15026 eliminates the need for an external freewheeling Schottky diode. The device also utilizes the on-resistance of the external low-side MOSFET as a current-sense element, eliminating the need for a current-sense resistor. This protects the DC-DC components from damage during output overload conditions or output short-circuit faults without the need for a current sense resistor.