US Patent 7821288 Circuit protecting apparatus and associated method, and circuit protecting layer

A circuit protecting apparatus is provided. The circuit protecting apparatus comprises a selecting module, a routing module, a processing module, and a controlling module. The selecting module selects for each of a plurality of a minimum-sized routing region a routing pattern from a plurality of predetermined routing patterns, and generates an input signal. The routing module then generates the routing comprising the selected routing patterns on a to-be-protected region to form a circuit protecting layer. The routing receives the input signal and outputs an output signal. The processing module decodes the output signal into a restored signal a compares the restored signal with the input signal to generate a comparison result, according to which the controlling module selectively fails a chip.