1. An inductor current estimator for a switching power supply, the inductor current estimator comprising: a first sensing/averaging component providing an average of a switch voltage at an input to the switching power supply; a second sensing/averaging component providing an average of an output voltage of the switching power supply; a subtraction component receiving the average of the switch voltage and the average of the output voltage; a first multiplying component receiving an output of the subtraction component and multiplying the output of the subtraction component by a first model parameter; a second multiplying component multiplying an input to the second multiplier component by a second model parameter; an adding component receiving an output of the first multiplying component and an output of the second multiplying component; and a delay component receiving an output of the adding component; an input to the second multiplier being an output of the delay component.