ALEXANDRIA, Va., March 21 -- Allegro MicroSystems, Manchester, New Hampshire, has been assigned a patent (No. 10,234,513, initially filed March 20, 2012) developed by eight co-inventors for a "magnetic field sensor integrated circuit with integral ferromagnetic material." The co-inventors are Ravi Vig, Bedford, New Hampshire, William P. Taylor, Amherst, New Hampshire, Andreas P. Friedrich, Metz-Tessy, Germany, Paul David, Bow, New Hampshire, Marie-Adelaide Lo, Chene-Bougeries, France, Eric Burde . . .