Patent ID: 8619451

Claim:
A content addressable memory (CAM) device for comparing a search key with a plurality of ternary words, comprising: an array having a plurality of rows of CAM cells and a respective row to store an associated ternary word, wherein each respective row is coupled to a corresponding match line, and wherein the associated ternary word embodies a binary data word masked by a local mask word; and a pre-compare memory having a plurality of rows of memory cells and a respective row to store a minimum data population count (D MIN ) and a maximum data population count (D MAX ) for a corresponding ternary word stored in the array, wherein D MIN indicates how many bits of the ternary word are of a same predetermined logic value, and D MAX indicates how many bits of the ternary word are of the same predetermined logic value plus how many bits of the ternary word have a don't-care value.