US Patent 7564262 - Mem-resistor Crossbar Comparator

http://www.freepatentsonline.com/7564262.html

Memory resistors are a new type of nanoscale circuit element which have been popularized in the last year due to interest by Hewlett Packard. One key advantage of mem-resistors is the ability to integrate data storage and signal processing functions in a single circuit element in order to achieve real time pattern recognition and control system functions. This patent teaches a crossbar circuit architecture using memristive junctions to perform an analog comparison function to achieve such real time responsiveness in applications such as audio/speech recognition and robotics. Further information is available at this link.
Claim 19 reads:

19. A device including:

a first plurality of crossbar columns storing first stored data in the form of high or low resistance states;

a second plurality of crossbar columns storing second stored data in the form of high or low resistance states; and

a summing amplifier electrically connected to an output row associated with one of the first or second plurality of crossbar columns, wherein the second stored data stored in the second plurality of crossbar columns have complementary values to the first stored data stored in the first plurality of crossbar columns.