Patent ID: 8598890
Filing Date: 2013-12-03
Classification: H01L

Abstract:
1. A system employing physical unclonable functions of an integrated circuit for detecting integrated circuits and protecting products and technology from integrated circuits which have been subject to tampering, stressing and replacement, comprising: the sensor detecting a characteristic impedance generated as a result of controlled access to a memory device of the integrated circuit, the characteristic impedance applied in creation of a discrimination matrix of values based on electrical interface signals for the integrated circuit; the sensor includes a ring oscillator and associated monitoring components, the ring oscillator is composed of the memory device of the integrated circuit and a sensory circuitry, wherein changes in a frequency generated by the ring oscillator is indicative of changes in circuitry; wherein the memory device is the delay function and the data values are equal to the address values and the frequency of the ring oscillator is a direct function of Address/Data pairs of the memory device of the integrated circuit and Address bits of the memory device are held constant and frequency of oscillation resulting from the ring oscillator is a function of the propagation delay and impedance of the Address bits and Data bits accessed under control of a control function.