A memristor-transistor hybrid ternary content addressable memory (MTCAM) with a memristor-based ternary memory cell is proposed. New emerging devices like memristors have recently been explored to overcome the limitations of CMOS-based memory circuits. The memristor is used as a binary memory cell in these MTCAM designs to replace a CMOS-based memory cell. This proposed design used a memristor as a ternary memory cell by exploiting its variable resistance characteristics. The associated wiring is reduced almost by a factor of 2 as a ternary cell is used instead of two binary cells. Area efficiency is further enhanced as the MTCAM cell is comprised of two transistors and two memristors (2T2M). A segmentation technique of match line along with a robust write/ search operation method is presented to enhance the search speed of the proposed MTCAM. Simulation based on a mathematical model of memristor is presented and analysed using 65 nm TSMC MOS model parameters. Corner simulations and Monte Carlo simulations are carried out to substantiate the robustness of the design against process variation. Simulation results show the worst search delay of 0.75 ns and the energy/bit/search of 0.866 fJ for the 128 � 128 bit MTCAM. 1 | INTRODUCTION Large data computation requires massive parallel processing with heavy memory access traffic [1,2]. Content addressable memory (CAM), a widely used hardware search engine for high-speed parallel data search applications [3], provides the capability to search data across an entire memory and returns the address in a single clock cycle [4,5]. Ternary content addressable memory (TCAM) adds more flexibility in the search operation by providing a third state called Mask ('don't care') state. The 'X' state provides a groupsearch option, that is, searching a portion of the word when necessary instead of searching the whole word. This additional 'X' state makes TCAM more powerful in searching by returning match condition regardless of the input search data [6]. TCAM, with its high throughput, is a promising solution for systems that deal with large data, such as a high-speed search engine, data base engine, data mining and multimedia processing [7-9]. CAM density has improved significantly over the past two decades with aggressive CMOS technology scaling [10]. Aggressive scaling of CMOS technology steadily increases the power density of the chip causing a heating problem [11,12]. TCAM needs 2-bit memory to accommodate the third state, 'X'. Multiple (12-16) transistors are thus needed to form TCAM cells, which require large area and, eventually, high power consumption [4]. This area and power constraint limits the usage of CMOS-based TCAM in network and classification applications [13,14]. New emerging devices such as magnetotunnelling junction-based devices [15], metamaterials-based optical nano circuits [16], carbon nanotube field effect transistors [17] and memristors [18,19] are being explored to find solutions for these area and power limitations of their CMOS counterpart. Memristor, among...

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