Single event upset hardened latch

摘要

A hardened latch capable of providing protection against single event upsets (SEUs) is disclosed. The hardened latch includes a first latch and a second latch that mirrors a subset of gates of the first latch. The second latch is inserted in the feedback path of the keeper circuit of the first latch and is cross-coupled with the gates of the keeper circuit of the first latch. The latch is hardened against single event upsets and an arbitrary number of successive SEUs attacking a single node, provided that the time between successive SEUs is larger than the recovery time of the latch. An alternate embodiment of the hardened latch includes a split buffer output. This embodiment is capable of reducing the propagation of erroneous transients. Another alternate embodiment of the hardened latch includes a Miller C buffer output. This embodiment is capable of reducing the propagation of erroneous transients below the level achievable in a hardened latch employing a split buffer output.