Phase current balancing for multiphase converters

摘要

A DC-DC converter includes a first differential voltage sensor to detect a first inductor current by sensing a first differential voltage across a first power stage of the DC-DC converter. A second differential voltage sensor detects a second inductor current by sensing a second differential voltage across a second power stage of the DC-DC converter. An integrator stage combines the first differential voltage from the first power stage and the second differential voltage from the second power stage to generate a compensation signal to adjust current balancing for the DC-DC converter.

主权项

1. A DC-DC converter, comprising a plurality of power stages:
a first differential voltage sensor to detect a first inductor current by sensing a first differential voltage between a first power stage of the DC-DC converter and a filtered pulse width modulated signal (PWM) that drives the first power stage by filtering a voltage at a switching node of the first power stage; a second differential voltage sensor to detect a second inductor current by sensing a second differential voltage between a second power stage of the DC-DC converter and a filtered pulse width modulated signal (PWM) that drives the second power stage by filtering a voltage at a switching node of the second power stage; and an integrator stage to combine the first differential voltage from the first power stage and the second differential voltage from the second power stage to generate a compensation signal to adjust current balancing between a plurality of power stages so that the current through each power stage is substantially equal for the DC-DC converter wherein current through each power stage is measured via the RIDS (ON) of transistors in the power stage.