Patent ID: 11875850
Assignee: MACRONIX INTERNATIONAL CO., LTD.
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 14:
15. A content addressable memory (CAM) memory cell including:
N1 memory cells (N1 being a positive integer larger than or equal to 3), wherein
the memory cell are serially connected, and a plurality of control terminals of the memory cells receive a plurality of search voltages indicating a search data; or
the plurality of control terminals of the memory cells receive a select voltage or a pass voltage, and a plurality of first terminals of the memory cells receive the search voltages via a plurality of signal lines; or
the plurality of control terminals of the memory cells are coupled to a plurality of word lines for receiving the search voltages, the first terminals of the memory cells are coupled to a match line and a pre-charge control circuit, and a plurality of second terminals of the memory cells are coupled to ground,
wherein a storage data of the CAM memory cell and the search data is a range storage data and a single-bit search data, or the storage data and the search data is a single-bit storage data and a range search data,
when the CAM memory cell is encoded for storing M1 decimal data combinations (wherein M1 being a positive integer, M1≥1 and M1≤N1), M1 memory cells of the memory cells are programmed to have a first threshold voltage, and (N1−M1) memory cells of the memory cells are programmed to have a second threshold voltage; and
the search data is defined by N2 search voltages (N2 being a positive integer larger than or equal to 3), when the search data is encoded for M2 decimal data combinations (wherein M2 being a positive integer, M2≥1 and M2≤N2), M2 search voltages of the search voltages have a first search voltage, and (N2−M2) search voltages of the search voltages have a second search voltage.