Colorado Springs-based Ramtron, a maker of nonvolatile, ferroelectric random access memory, announced today that it has been issued U.S. Patent No. 7,672,151. The firm said the patent, entitled "Method for Reading Non-volatile Ferroelectric Capacitor Memory Cell" materially expands its intellectual property portfolio. According to the USPTO, the patent was granted Tuesday to Joseph T. Evans Jr., William D. Miller, and Richard H. Womack, all of Albuquerque, New Mexico. The patent has been in the work for more than 20 years -- having been filed in July of 1989, as an offshoot of another patent which was filed in 1987.