Patent ID: 8837189
Filing Date: 2014-09-16
Classification: G11C

Abstract:
1. A content addressable memory (CAM) device, comprising: a non-volatile memory array having a plurality of non-volatile memory cells arranged in a plurality of NAND architecture memory cell strings; a search word register having an inverting and non-inverting output for each bit position of the search word register, wherein each output of the search word register is coupled to a plurality of word lines of the plurality of NAND memory cell strings; a source line coupled to one or more source-side connections of the plurality of NAND memory cell strings; and a plurality of match lines, each match line coupled to a drain-side connection of a NAND string of the plurality of NAND strings; wherein each NAND memory cell string of the plurality of NAND memory cell strings stores a data word in a plurality of CAM memory cell structures and where each CAM memory cell structure is formed from a paired first and second non-volatile memory cells of the NAND memory cell string; wherein a control gate of the first non-volatile memory cell of each CAM memory cell structure is coupled to a non-inverting output of a selected bit position of the search word register and a control gate of the second non-volatile memory cell is coupled to an inverting output of a selected bit position of the search word register; and wherein the CAM memory device is adapted to couple a voltage of the source line through a NAND memory cell string to its coupled match line when a data word stored in the NAND memory cell string matches an input data word stored in the search word register.