The method comprises forming barrier layers of AlxGa1-xAs, forming a quantum well layer of InGaAs between the barrier layers, and forming an interfacial layer between the quantum well layer and each of the barrier layers. The invention eliminates the need to keep all the packets of data queued until the acknowledge message for that data has arrived. A first diode is coupled in forward direction between the first node of the H-bridge and the input node of the boost converter.