Method and device for testing a chain of flip-flops

An electronic device for testing a chain of flip-flops, the electronic device comprising:

• a generation circuit comprising:
• a plurality of reference generation circuits, each configured to generate a different intermediate reference signal from a cyclic test pattern;
• wherein the plurality of reference generation circuits are replicas of one another;
• and
• a majority vote circuit receiving the different intermediate reference signals from each of the plurality of reference generation circuits, the majority vote circuit configured to generate a reference signal as matching a majority of the different intermediate reference signals;
• wherein the chain of flip-flops receives the reference signal from the majority vote circuit and produces a flip-flop output as the reference signal propagates through the chain of flip-flops;
• and
• a processing circuit comprising:
• a plurality of intermediate processing circuits, each configured to receive the flip-flop output from a last flip-flop of the chain of flip-flops, to compare the flip-flop output to the reference signal, and to generate a different intermediate output signal at an output indicating whether at least one flip-flop of the chain of flip-flops is defective;
• wherein the plurality of intermediate processing circuits are replicas of one another;
• a majority vote circuit receiving the different intermediate output signals from each of the plurality of intermediate processing circuits, the majority vote circuit configured to generate an output signal as matching a majority of the different intermediate output signals;
• and
• wherein the output signal indicates whether at least one flip-flop of the chain of flip-flops is defective.