Patent ID: 8008659

Claim:
A semiconductor integrated circuit device comprising: a leakage detecting circuit which includes a plurality of leakage detecting MOSFETs and which detects components of leakage current of the plurality of MOSFETs; a control circuit which outputs a control signal depending on a detection result from the leakage detecting circuit; and a substrate bias generating circuit which changes a substrate bias of a semiconductor substrate depending on the control signal, wherein the substrate bias is controlled such that a ratio of a subthreshold leakage current component including a subthreshold leakage current of a first one of the plurality of leakage detecting MOSFETs to a substrate leakage current component including a substrate leakage current of a second one of the plurality of the leakage detecting MOSFETs is a predetermined value, and wherein the first and second ones of the plurality of leakage detecting MOSFETs detect different leakage current components.