Design of Magnetic Non-Volatile TCAM With Priority-Decision in Memory Technology for High Speed, Low Power, and High Reliability

Abstract

Recently, various magnetic non-volatile ternary content-addressable memory (MNV-TCAM) cells that use magnetic tunnel junctions (MTJs) as storage units have been proposed to realize zero standby power. However, they still suffer from low reliability and high power consumption for search operation. In addition, the restrictions on the ordering of the TCAM array required by the using of the priority encoder to resolve the multiple match problem due to the `X' results in large delay and high energy consumption for update operation. To address these issues, the novel MNV-TCAM cell is first proposed, aiming to achieve high-speed, low-power, and high-reliable search operation. In addition to the search data operation, it can realize a search length operation. By exploiting this search length operation, we then present circuit-level design of the MNV-TCAM with a priority-decision in memory technology, which can utilize the length information of matched words sorted in an arbitrary order to decide the highest-priority matched word by performing a three-phase search operation. It implies that the restrictions on the ordering can be eliminated, thus, improving the update speed and energy-efficiency. Finally, hybrid CMOS/MTJ simulations are performed to demonstrate its functionality and evaluate its performance in terms of search reliability, search speed, and search energy consumption.