Patent ID: 11967377
Assignee: MEDIATEK SINGAPORE PTE. LTD.
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 0:
1. A content addressable memory (CAM) device, comprising:
a plurality of CAM sub-banks, each CAM sub-bank comprising:
an array of CAM cells arranged in rows and columns and partitioned into a first stage and a second stage along a column dimension;
a plurality of first-stage match lines (MLs) coupled to the respective rows of CAM cells in the first stage, each first-stage ML to indicate whether a match is found in a corresponding first-stage row segment for a first portion search key;
a plurality of first-stage search line (SL) pairs in the first stage;
a plurality of second-stage MLs coupled to the respective rows of CAM cells in the second stage;
a plurality of second-stage SL pairs coupled to the respective columns of CAM cells in the second stage;
a circuit operative to receive all of the first-stage MLs as input and generate an SL enable (SL_EN) signal as output, wherein the SL_EN signal is a gating signal for the plurality of second-stage SL pairs, the circuit is further operative to de-assert the SL_EN signal when none of the first-stage MLs indicate a match, wherein de-assertion of the SL_EN signal blocks a second portion search key from being provided to the second-stage SL pairs; and
an output circuit operative to indicate a match between a search key and data stored in one or more rows in the CAM sub-banks, wherein the search key includes the first portion search key provided to the first stage and the second portion search key provided to the second stage.