Designing chaotic circuits is prerequisite to chaotic communications
chaotic encryption etc.Therefore the fundamental research on it is extremely significant.This paper generalizes the method of designing 2D chaotic circuit proposed by the authors before.By this new method
it becomes simple and flexible to design chaotic dynamic systems in the 3D state space.The remarkable advantage of this design method is that one can choose complexity of the chaotic attractor as needed by combining the three kinds of modules
and the chaotic attractor can be easily implemented with a circuit or an integrated circuit.