Abstract: The disclosure describes the use of a neural network circuit, such as an oscillatory neural network or cellular neural network, to serve as a physically unclonable function on an integrated circuit or within an electronic system. The manufacturing process variations that impact the initial state of the neural network parameters are used to provide the unique identification for the physically unclonable function. A challenge signal to the neural network results in a response that is unique to the circuits process variations. The neural network is designed such that there are random variations among manufactured circuits, but that the specific instance variations are sufficiently deterministic with respect to circuit aging and environmental conditions such as temperature and supply voltage.