A circuit includes a current sensor circuit having inputs and an output. The current sensor inputs are adapted to be coupled to inductor terminals a power converter. The current sensor circuit includes a tunable time constant circuit coupled between the current sensor inputs and the current sensor output. A time constant control circuit is coupled to a tunable time constant circuit, and is configured to tune the time constant circuit responsive to the current sensor output and another signal representative of inductor current. An adjustable gain circuit has a first input coupled to the current sensor output. A direct current resistance (DCR) control circuit has an output coupled to a second input of the adjustable gain circuit, and the DCR control circuit is configured to provide a gain adjust signal at the output thereof responsive to an average current of the inductor and a current command signal for the power converter.