A device for determining the version of metal mask utilized for producing
a given metal layer (Metal3) in an integrated circuit including a
plurality of metal layers (Metal0, . . . , Metal3), and any modification
made to the given metal layer (Metal3) requiring generation of a new
version of the corresponding metal mask. The device includes a cell
(Cell) integrated into the metal layer (Metal3) including at least a
first voltage source (Vdd) for supplying a first voltage level, at least
a second voltage source (GND) for supplying a second voltage level, and
an output bus composed of at least one conductor wire (S1, S2) connected
selectively to one of the first and second voltage sources as a function
of the version of metal mask used to produce the metal layer, so as to
generate a binary output signal representative of the mask version
utilized.