Identification Circuit

摘要

An identification circuit is provided for generating a unique identification pattern for an object to be identified. The circuit includes at least one bistable closed circuit ring that includes a plurality of switching stages, each switching stage having at least two parallel internal signal delay paths, which are connected directly to one another on the input side and are selectable on the output side by at least one challenge bit of a challenge word applied to the circuit ring. Each internal signal path has a production-determined individual signal transit time, wherein a reset element which shifts a downstream switching stage temporarily into an unstable state is provided for each switching stage. The switching stages transition out of the respective unstable states on the basis of signal transit times, which may be read out as a response word that forms the unique identification pattern for the object to be identified.

主权项

1. An identification circuit for producing an explicit identification pattern for an object that is to be identified, the identification circuit comprising:
at least one bistable closed circuit ring comprising a plurality of switching stages, wherein each switching stage of the circuit ring comprises at least two parallel internal signal delay paths, each internal signal delay path having a respective input side and output side, wherein the input sides of the at least two parallel internal signal delay ahs are connected to one another directly and the output sides are configured to be selected by at least one challenge bit of a challenge word applied to the circuit ring, wherein each internal signal path of each switching stage comprises a manufacture-dependent individual signal propagation time, wherein each switching stage of the circuit ring comprises a respective reset element that puts a downstream switching stage of the circuit ring temporarily into an unstable state, wherein the switching stages of the circuit ring change from respective unstable states to stable states on the basis of the signal propagation times selected by the applied challenge word, the stable states being configured to be read as a response word that forms the explicit identification pattern for the object that is to be identified.