Logic architecture for single event upset immunity

Abstract

An SEU immune logic architecture includes a dual path logic gate coupled to a dual to single path converter. A first and a second logic element within the dual path logic gate are functionally and possibly structurally equivalent, and are coupled to receive input signals spanning redundant input signal sets. A given logic structure within the first logic element may receive specified input signals within a particular input signal set, while an analogous logic structure within the second logic element may receive corresponding input signals within the counterpart input signal set. A radiation induced transient pulse that affects one input signal may affect an output signal asserted by one logic structure; however, since the transient pulse doesn't affect a corresponding input signal applied to the analogous logic structure, the dual path logic gate may output at least one correctly valued signal when a transient pulse occurs. The dual to single path converter is coupled to receive signals output by the dual path logic gate. In the event that a transient signal appears at an input of the dual to single path converter, a current path may be interrupted, and a correct output signal value is maintained as a result of stray capacitance present at an output node.