15-T 셀 기반의 저 전력 TCAM 설계 = Design of Low Power TCAM Based on 15-T Cell

다국어 초록 (Multilingual Abstract)

Ternary content-addressable memory (TCAM) is a high-speed search memory used for high-speed applications. A large capacity TCAM increases the bit and address of the word, which increases the number of match lines and search lines, and capacitance. We propose a 15-T TCAM cell that reduces the capacitance of the match line and an 128 bit × 128 bit TCAM that applies the selective match line charging technique to reduce the power consumption of the match line. The proposed circuit is verified through the HSPICE with 0.18um CMOS technology. The minimum cycle time increased by 28.2%, the match line energy (fJ/bit/search) decreased by 48.5% and the EDP (Energy Delay Product) decreased by 28.4% compared to the previous selective match line charging scheme. Also, the 1-bit mismatch match line, which is a risk factor in steady operation, has a voltage margin of 0.53V as compared with the match line of the match condition.

국문 초록 (Abstract)

TCAM(Ternary content-addressable memory)은 빠른 속도를 요구하는 응용분야에 사용되는 고속 검색 메모리이다. 대용량의 TCAM은 워드의 비트와 어드레스가 증가하여 매치라인과 서치라인의 수 즉, 커패시턴스가 증가한다. 본 논문에서는 매치라인의 전력소모를 감소시키기 위하여 매치라인의 커패시턴스를 감소시킨 15-T TCAM 셀과 선택적 매치라인 충전기법을 적용시킨 128비트×128비트 TCAM을 제안한다. 제안한 회로는 0.18um CMOS 공정을 사용하여 설계하였으며 HSPICE를 통해 타당성을 검증하였다. 이전의 선택적 충전 매치라인 기법과 비교하여 최소 사이클 시간은 28.2% 증가하였고 매치라인의 에너지 (fJ/bit/search)는 48.5% 감소하였으며 EDP(Energy Delay Product)는 28.4% 감소되었다. 또한 정상동작의 위험요소인 1 비트 미스매치상태의 매치라인은 매치상태의 매치라인과 0.53V의 전압 마진을 가진다.

참고문헌 (Reference)

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