This paper has proposed a new energy based switching scheme for controlling DC-DC buck converter circuits and analysed its stability. There are three modes of operations, and the switching among these three modes depends on the reference voltage and the inductor reference current. The inductor reference current is calculated by the principle of energy balance. The reference voltage is designed to ensure that the voltage ripple as well as average value of the output voltage remain approximately constant in response to line and load disturbances. The phase plane analysis and sensitivity matrix analysis show that the proposed control scheme is free from chaos and in fact has a super-stable orbit.