Abstract
Power cycling of a point-of-load converter is observed during system-level heavy ions tests. This event has low cross section and is observed for reduced supply voltage of the device under test. Laser tests are used to reproduce this effect and show that it might be due to propagation of single-event transients from the voltage reference to the operational amplifier being part of the undervoltage protection circuit. Laser tests show that propagating transients are the ones with a high enough positive peak and an insignificant negative peak value, whereas some transients with a bigger maximum and/or peak-to-peak value do not propagate. SPICE simulation shows that in an operational amplifier with low voltage difference between V + and V - , there is a difference in the propagation of unipolar and bipolar transients from the input to the output of the amplifier. Analysis of the voltage-controlled current source in the amplifier also explains the difference in propagation of bipolar transients with a negative peak followed by a positive peak and with a positive peak followed by a negative peak.