Low noise integrated circuit device for reducing a noise on LSI power supply nets to supply electric charges required to operate IC

摘要

A condenser having a huge area is required to reduce a noise on LSI power supply nets (−&Dgr;VDD) of an integrated circuit because a bypass condenser can only utilize a part of accumulated electric charges. A noise of LSI power supply nets is suppressed by generating a noise of a reversed polarity (+&Dgr;VDD) to the noise on the LSI power supply nets (−&Dgr;VDD), based upon a noise reducing circuit discharging a condenser charged with a high voltage. A noise reduction effect equivalent to a bypass condenser having a large capacity is obtained even when a condenser having a small capacity is used.