Automatic cell placement and routing apparatus and automatic cell placement and routing method used for the apparatus

Abstract

A buffer cell and an inverter cell are embedded in advance in an internal open space of each of mega-cells and IO cells composing a semiconductor integrated circuit. Thereafter, in cases where it is expected that a cross-talk noise is generated in a signal transmitting through a particular wire of the semiconductor integrated circuit, one mega-cell or one IO cell, which is placed in a position nearest to a generation position of the cross-talk noise, is selected from the mega-cells and the IO cells, and the buffer cell or the inverter cell embedded in the selected mega-cell or the selected IO cell is inserted into the particular wire. Therefore, because the capacitance between the particular wire and each wire adjacent to the particular wire is reduced, the cross-talk noise can be reduced.