A Low-Power Ternary Content Addressable Memory With Pai-Sigma Matchlines

This paper proposes a Pai-Sigma matchline scheme to reduce the compare (search) power of a ternary content addressable memory (TCAM). The proposed matchline does not incur the issues of charge sharing and short circuit current, which typically exist in the hybrid nand-nor matchline. Moreover, the switching activity of the search lines of a TCAM with the proposed matchlines is low. A 32×64-bit TCAM with the Pai-Sigma matchlines is implemented to demonstrate the low-power feature. Results show that the compare power of the TCAM can achieve 60% energy reduction compared with the conventional nor-type TCAM. Also, the energy consumption per bit per search of the TCAM is only 2.287 fJ/bit/search.