Patent ID: 8970247
Filing Date: 2015-03-03
Classification: G06F,H01L,H03K

Abstract:
1. A semiconductor integrated circuit device comprising: a semiconductor substrate; a circuit block formed on said semiconductor substrate; an electrically conductive pattern formed on at least a portion of said circuit block that is to be protected, with said portion to be protected being between said electrically conductive pattern and said semiconductor substrate; an oscillation circuit connected to said electrically conductive pattern, and configured to oscillate at an oscillation frequency determined by a circuit constant of said electrically conductive pattern; and a detection circuit configured to test the oscillation frequency of said oscillation circuit to determine whether the oscillation frequency of said oscillation circuit lies with a preset range, and to make a determination that said electrically conductive pattern has been altered if the oscillation frequency does not lie within the preset range, wherein said detection circuit comprises a counter circuit which counts the oscillation frequency of said oscillation circuit.