Patent ID: 7453281

Claim:
A circuit which causes disruption in an integrated circuit (IC) when operatively coupled to the IC, the circuit comprising: a first element having a first input for receiving a first signal ( 110 ) which is generated by at least a first oscillator and a second input for receiving a second signal ( 120 ), and a first output coupled to an input of a second element ( 150 ), the first element generates a third signal ( 140 ) on the first output when the first and second signals satisfy a predetermined condition; the second element comprises a second output ( 160 ) coupled to the IC ( 170 ); at least one of the first or second element appears to be coupled to the IC in a view of the circuit: the circuit being inoperative when at least one of the first or second element is not operatively coupled to the IC; the circuit being operative when the first and second element are operatively coupled to the IC; and wherein the circuit is not coupled to the IC when the first oscillator comprises a camouflage circuit.