An embodiment system comprises a physical unclonable function device, wherein the device comprises a first assembly of non-volatile memory cells each having a selection transistor embedded in a semiconductor substrate and a depletion-type state transistor having a control gate and a floating gate that are electrically connected, the state transistors having respective effective threshold voltages belonging to a common random distribution, and a processing circuit configured to deliver, to an output interface of the device, a group of output data based on a reading of the effective threshold voltages of the state transistors of the memory cells of the first assembly.