Patent ID: 7715228

Claim:
A ferromagnetic thin-film based digital memory system having memory cells selected through voltage values supplied coincidentally on interconnections made thereto, said memory comprising: a plurality of ferromagnetic thin-film based bit structures, each supported on a substrate and separated from one another by spacer material therebetween, each said bit structure being capable of being switched successively between alternative electrical resistance states by switching voltages having magnitudes exceeding switching voltage thresholds thereof and that are selectively applied between first and second ends of said bit structures so as to provide suitable polarity thereacross, and each said bit structure being capable of having a current electrical resistance state thereof determined by measurement voltages of magnitudes less than said switching voltage thresholds and that are selectively applied between said first and second ends thereof; a plurality of word line structures each having a pair of word line end terminal regions adapted to conduct electrical current therethrough with each of said pairs of word line end terminal regions having an electrical conductor connected therebetween which is electrically connected to each said first end of those of said plurality of bit structures that are in a corresponding one of a plurality of word line fractions of said plurality of bit structures; a plurality of bit line structures each having a pair of bit line end terminal regions adapted to conduct electrical current therethrough with each of said pairs of bit line end terminal regions having an electrical conductor connected therebetween which is electrically connected to each said second end of those of said plurality of bit structures that are in a corresponding one of a plurality of bit line fractions of said plurality of bit structures, and with there being a said bit structure from each of said plurality of word line fractions in each said bit line fraction and a switching system, suited for electrical connection to a source of voltage, and selectively electrically connected to each of said word line and bit line end terminal regions, said switching system being capable of selectively providing at selected state change ones of said word line and bit line end terminal regions said switching voltages of selected polarities, and further capable of providing reference voltages at selected said word line and bit line end terminal regions other than said selected state change ones thereof having magnitudes that are selected multiples or fractions, or both, of said magnitudes of said switching voltages.