An MRAM circuit includes an MRAM array having a plurality of operational MRAM elements and a reference cell made up of one or more reference MRAM elements. A plurality of program lines within a first region are cladded with a flux-concentrating layer configured to focus a generated magnetic field while the portions of the program lines within a second region are uncladded so that the generated magnetic field is unfocused. Generally, the first region is associated with the operational MRAM elements and the second region is associated with the reference cell.