Buck controller for 4.5V to 40V rails
Switching frequency is programmable from 100kHz to 1MHz via a single resistor, letting the designer trade efficiency against inductor and capacitor size. The synchronous rectifier driver improves efficiency at higher output currents compared to a diode-based freewheel path. Control features include current limiting, an enable pin for sequencing, frequency control, and a power-good flag for output-rail monitoring. The 87.5% maximum duty cycle sets the practical step-down ratio.
