Tohoku Univ. Technology：A Nonvolatile Register with a Differential Information Storing Scheme：T24-080

Reduction in power consumption and area with conventional level of short operating time

Intermittent computing enables continuous processing under unstable energy supply. In edge device implementation, a nonvolatile logic circuit using nonvolatile registers is promising as it retains internal state with only local data transfers.　 Conventional nonvolatile registers, composed of multiple 1-bit memory circuits (NV-FFs), require two MTJ devices per bit, leading to high area and energy overhead. The reference-load sharing scheme (RLSS) was proposed to solve this issue, however, a new issue arose as the required operation time increased in proportion to the number of register bits. This invention introduces a differential information storage scheme (DISS), which stores 1-bit data via resistance differences between adjacent MTJ devices. This allows two-cycle backup and restore, reducing energy and area while maintaining conventional operation speed, as confirmed by simulations.

others