Single event transient propagation through digital optocouplers

A new approach for assessing the risk of upsetting digital optocouplers due to the propagation of single event transients (SETs) is proposed. The optocoupler's input current (I/sub f/) and propagation time (t/sub pHL/) are found to be the most critical parameters for this approach. A case study using the 6N140 optocoupler and SETs measured at the output of the National Semiconductor LM139 is detailed to validate the concept.