Abstract: This paper deals with a perfect digital circuit theory by using only one algebra which keeps to follow the Boolean algebra s laws and overcomes the difficulty with which the Boolean algebbra is faced. The new theory provides a good expression of any realistic circuit s structure which contains the signal, network and load. Several theorems on the switch operators ,||, and on the relations to transform from one type of circuits into another are proved. Based on these theorems a state equation method is proposed for analyzing dynamic circuits.