Abstract
This article proposes two quadruple node upset (QNU) recoverable latches, namely QNU-recoverable and high-impedance-state (HIS)-insensitive latch (QRHIL) and QRHIL-LC (low-cost version of the QRHIL), for highly robust computing in harsh radiation environments. First, the QRHIL that mainly consists of a 5×5 looped C-element matrix is proposed. Then, to reduce overhead, the QRHIL-LC that mainly uses 24 interlocking C-elements is proposed. Both latches can self-recover from any QNU, while the QRHIL-LC has a low cost compared to the QRHIL. Simulation waveforms show the QNU-recoverability of the proposed QRHIL and QRHIL-LC latches. Moreover, compared with the QRHIL latch, the QRHIL-LC can approximately save power dissipation by 16% and silicon area by 5%.