Programmable Step-Down Switching Voltage Regulators with Adaptive Power MOSFETs

摘要

A step-down switching voltage regulator includes M high-side switches connected between an input voltage and a node; N synchronous rectifiers connected between the node Vx and a ground voltage and an inductor connected between an input voltage and a node Vx and an inductor connected between the node Vx and an output node. An interface circuit decodes a control signal to identify: 1) a subset (m) of the high-side switches, 2) a subset (n) of the synchronous rectifiers. A control circuit drives the high-side switches and synchronous rectifiers in a repeating sequence that includes an inductor charging phase where the high-side switches in the subset m are activated to connect the node Vx to the input voltage; and an inductor discharging phase where the synchronous rectifiers in the subset n are activated to connect the node Vx to the ground voltage.