Patent ID: 7380183

Claim:
A device comprising: a plurality of scan flip-flops forming a scan chain, each of the flip-flops having a data input and a scan input connected functionally to control, respectively, a data output and a scan output, in accordance with a clock signal; a first circuit receiving as inputs a first data signal and a first circuit select signal, the first circuit being constructed so as to output a second data signal; a first flip-flop belonging to said scan chain and outputting a third data signal at the data output of the first flip-flop, the data input of the first flip-flop receiving the first data signal; a second flip-flop belonging to said scan chain and outputting a first selector signal at the data output of the second flip-flop, the data input of the second flip-flop receiving the first circuit select signal; and a first selector receiving said second data signal and said third data signal as data inputs, the first selector receiving the first selector signal as a selection input, the first selector outputting one of said second and third data signals based on a level of the first selector signal.