Patent ID: 8471612

Claim:
Signal value storage circuitry comprising: transparent storage circuitry having a signal input and a signal output, said transparent storage circuit controlled by a pulse clock signal: (i) during a transparent phase of said pulse clock signal, to transmit a transition in a signal received at said signal input to said signal output via a signal node; and (ii) during a non-transparent phase of said pulse clock signal, to block transmission of said transition of said signal through said signal input while maintaining a previously captured signal value at said signal output; transition detector circuitry coupled to said signal node within said transparent storage circuitry and configured to generate a detection pulse with a detection pulse width T PW when a signal transition is detected at said signal node; and error detecting circuitry coupled to said transition detecting circuitry and configured to generate an error indicating signal when said detection pulse overlaps in time with said non-transparent phase for at least an overlap period T OV .