Design of MRAM-Based Magnetic Logic Circuits

Emerging technologies are gaining an increasing attention due to the slowdown of CMOS development. NanoMagnet Logic (NML), among emerging technologies, increases the potentials for developing fully magnetic circuits. Using a magnet as a building block for logic circuits has the advantage to merge logic and memory in the same device. Moreover, circuits have low dynamic and no stand-by power consumption. Even though demonstrations exist for small circuits, the experimental feasibility of complex NML circuits still represents a critical point for this technology. In this paper, we outline the possibility to design NML circuits based on the technological structure of magnetic RAMs (MRAMs). NML circuits based on MRAMs rely on a well-developed technology that provides a natural interface with CMOS world. To study this new NML implementation a novel tool, NANOcom, was developed to easily design complex circuits. Simulations were then performed using an high-level behavioral model described using VHDL language. Two types of circuit layouts, based on different technological constraints, are investigated. To evaluate the performance of this new NML implementation, a 4-bit Galois multiplier is used as a testbench. The Galois multiplier is the basic block of cryptographic circuits, an ideal target for this technology. Results obtained are encouraging and can unlock interesting options for the future development of NML technology.