That is the computer aided design (CAD) ofelectronic circuit in 70s, the computer aided engineering (CAE) in 80s and theelectronic system design automation (ESDA) in 90s.

• 电子线路的CAD（计算机辅助设计）是EDA发展的初级阶段，80年代初期，形成了CAE--计算机辅助工程。 也就是所谓的EDA技术中级阶段。