Programmable Step-Up Switching Voltage Regulators with Adaptive Power MOSFETs

摘要

A step-up switching voltage regulator includes an inductor connected between an input voltage and a node Vx, M low-side switches connected between the node Vx and a ground voltage and N synchronous rectifiers connected between the node Vx and an output node. An interface circuit that decodes a control signal to identify: 1) a subset (m) of the low-side switches, 2) a subset (n) of the synchronous rectifiers, and 3) a reference voltage V_ref. A control circuit drives the synchronous rectifiers and low-side switches in a repeating sequence that includes an inductor charging phase where the low-side switches in the subset m are activated to connect the node Vx to the ground voltage; and an inductor discharging phase where the synchronous rectifiers in the subset n are activated to connect the node Vx to the output node.