1. Downhole equipment circuitry, comprising:a first substrate member including one or more circuits;
a second substrate member including one or more circuits; and
a flexible circuit, wherein:
the first and second substrate members are separate substrate members;
the flexible circuit is of a laminated construction with a plurality of layers, wherein the flexible circuit is of a rigid-flexible type such that at least one rigid portion of the flexible circuit has at least one rigid layer that is mounted with respect to the first or second substrate members; and
the flexible circuit provides electrical communication between the one or more circuits of the first substrate member and the one or more circuits for the second substrate member.