US Patent 10060973 Test circuits for integrated circuit counterfeit detection

Described herein are various technologies pertaining to identifying counterfeit integrated circuits (ICs) by way of allowing the origin of fabrication to be verified. An IC comprises a main circuit and a test circuit that is independent of the main circuit. The test circuit comprises at least one ring oscillator (RO) signal that, when energized, is configured to output a signal that is indicative of a semiconductor fabrication facility where the IC was manufactured.