Inductor current measurement compensation for switching voltage regulators

摘要

A current estimation method for a switching voltage regulator that delivers current to a load through an inductor includes measuring a voltage across a capacitor of an RC current sense network coupled in parallel with the inductor, generating an estimate of the current through the inductor based on the voltage measured across the capacitor of the RC current sense network and adjusting the estimate of the current through the inductor by a compensation filter that compensates for variation in the inductance of the inductor as a function of at least one of temperature and current.

主权项

1. A method of current estimation for a switching voltage regulator that delivers current to a load through an inductor, the method comprising:
measuring a voltage across a capacitor of an RC current sense network coupled in parallel with the inductor; generating a digitized current value which estimates the current through the inductor, based on the voltage measured across the capacitor of the RC current sense network and a specified DCR (non-ideal DC resistance) value for the inductor at nominal conditions; and adjusting the digitized current value by a compensation filter that compensates for at least one of temperature and current variation of the specified DCR value and the inductance of the inductor.