A study of transient radiation effects on the response of standard and radiation-hardened integrated-circuit operational amplifiers in an electron beam.

Abstract

This study investigates the effects of 1-µsec pulses of 80-90 Mev electrons on the standard µA709 operational amplifier and its radiation-hardened version, the µA744. The transient responses from the electron beam and from electronic pulses were investigated and compared for each amplifier. Also investigated were the responses of dielectrically isolated NPN and PNP transistors contained in the µA744, which were further compared with responses obtained from discrete NPN and PNP transistors. The overall transient radiation responses of the µA709 and µA744 amplifiers, with several exceptions, were not very different. The same can be said for a comparison of the responses from the µA744 and discrete NPN and PNP transistors. Based on this study the µA744 is not superior to the µA709 by virtue of its radiation hardening. It should be noted however, that the µA709 is driven into oscillation by the electron beam while the µA744 is not.