Spintronic Switches for Ultralow Energy On-Chip and Interchip Current-Mode Interconnects

Energy efficiency and design complexity of long-distance on-chip and interchip data links can be a major bottleneck for high-performance computing systems. As a solution, we propose an ultralow energy interconnect design using nanoscale spin-torque switches. In the proposed method, data is transmitted in the form of current pulses with amplitude of the order of microamperes that flow across a small terminal voltage of <;100 mV. Subnanosecond spin-torque switching of scaled nanomagnets (such as domain wall switch or lateral spin valves) can be used to receive and convert such high-speed current-mode signal into binary voltage levels using magnetic tunnel junction with the help of a simple CMOS inverter. As a result of low-voltage, low-current signaling, and minimal signal-conversion overhead, the proposed technique can facilitate highly compact design of multigigahertz interchip and on-chip datalinks. Such interconnects can be more than ~ 100× energy efficient compared with state-of-the-art CMOS interconnects.