Semiconductor integrated circuit apparatus and method for designing the

Abstract

A semiconductor integrated circuit device is provided which include a plurality of cell columns each having a number of unit cells previously fabricated on a semiconductor substrate selected from the plural kinds of unit cells which are formed in desired circuits by electrically connecting circuit devices previously arranged. Each column includes at least one kind of unit cell of a dynamic circuit which has a node in a floating state during the operation of the cell unit. A fixed potential shield layer is also provided on the cell columns so as to cover the nodes of the dynamic circuits. By virtue of this, a wiring area for electrically connecting the desired cell units can be located between the cell columns and above the shield layer. In other words, signal wirings in the wiring area can pass over the nodes of the dynamic circuits. without adverse parasitic effects. The unit cell can also be provided with a precharge circuit comprising a standard cell and an in-cell wiring layer. Further, clock input terminals of the unit cells which are provided with a precharge circuit can be divided into plural groups, with all of said clock input terminals belonging to the same group and having equal load capacitances being connected. Clock buffer cells can be provided for supplying clock signals to the clock signal wirings for each group.