Fully Digital Ternary Content Addressable Memory using Ratio-less SRAM Cells and Hierarchical-AND Matching Comparator for Ultra-low-voltage Operation

Abstract

A 36-bit x 32-entry fully digital ternaly content addressable memory (TCAM) using the Ratio-less 12transistor SRAM (RL-12T-SRAM) technology and fully complementary hierarchical-AND matching comparators (HAMCs) was developed for ultra-low-voltage operation. The minimum operating supply voltage of 0.25V which is the less than half of the conventional TCAM was experimentally confirmed by the developed test chip.

Design and measurement of fully digital ternary content addressable memory using ratioless static random access memory cells and hierarchical-AND matching comparator

“…Since the 6-transistor SRAM cells and the MLSA in the conventional TCAM suffer from device variabilities especially in the lowsupply voltage range, we have developed the ratioless TCAM cell and a fully complementary hierarchical-AND matching comparator (HAMC). 29,30) We have developed a test chip including the proposed TCAM and conventional TCAM and confirmed the operation of the power supply voltage of 0.25 V. 31) In addition to the design of RL-TCAM, we also disclose the technique of measuring the TCAM function with a digital LSI tester in such an ultra low-voltage region in this paper.…”