Yield and energy tradeoffs of an NVLatch design using radial sampling

Abstract

Nonvolatile latches are increasingly popular with the advent of IoT design. We study the yield energy tradeoff of the backup mechanism of an STT-MTJ based nonvolatile latch. For the yield analysis, we rely on Hicks and Wheeling methodology for multi-cone radial sampling for the purpose of rare fail estimation. Yield is shown to be delimited by the Parallel-to-AntiParallel magnetic angle transitions. To accommodate for the slower cells, we note an increase in the average energy requirements for the backup mechanism. Simulations indicate an increase of 10%-40% for the average energy requirements to achieve an ideal yield requirement close to 99% for different number of components.