Patent ID: 9047950
Filing Date: 2015-06-02
Classification: G11C,H01F,H01L

Abstract:
1. A voltage-controlled magnetic anisotropy (VCMA) magnetoelectric content addressable memory (CAM) apparatus, comprising: an array of magnetoelectric content addressable memory (CAM) cells, wherein each cell receives two word lines, a bit line, a match-line, complementary source lines, a switched supply voltage and a ground; at least two complementary magnetoelectric tunnel junctions (MEJs), comprising a first MEJ and a second MEJ in each of said CAM cells, each MEJ having at least two ferromagnetic (FM) layers separated by a dielectric (DE) layer, and in which said at least two FM layers comprise at least an FM fixed layer and an FM free layer; and a transistor circuit which during a write pulls the switched supply voltage low, with the first MEJ written in response to a switching voltage applied to the bit line and asserting a first word line, while the second MEJ is written by applying a complementary switching voltage to the bit line and asserting a second word line; said transistor circuit during a read operation grounds the two word lines and the bit line while holing V said transistor circuit having a precharge phase of a read operation in which the match line is precharged high and left floating during a subsequent evaluation phase; wherein search bits having a data bit and its complement are applied to the complementary source lines during an evaluation phase of content addressability in which the match line is pulled low in response to a mismatch, in which data searched for does not equal data stored in said CAM); and wherein it is not possible for the read operations performed during searching of said CAM apparatus to switch the MEJs, because writing of the MEJs in said CAM apparatus were performed with an opposite polarity as reading of the MEJs during search.