“Power amplifier” in this disclosure refers to a switched-mode converter that generates a sinusoidal output at the switching frequency from a dc input. A conventional boost power amplifier contains two matched inductors, each connected between the input source and a grounded switch. Larger inductance would reduce steady-state ripple current at the expense of dynamic bandwidth that is inversely proportional to the square root of the inductance. The disclosure demonstrates that dynamic bandwidth is significantly improved by inversely coupling the inductors.