This paper presents two circuits to measure pulse width distribution of single event transients (SETs). We first review requirements for SET measurement in accelerated neutron radiation test and point out problems of previous works, in terms of time resolution, time/area efficiency for obtaining large samples and certainty in absolute values of pulse width. We then devise two measurement circuits and a pulse generator circuit that satisfy all the requirements and attain sub-FO1-inverter-delay resolution, and propose a measurement procedure for assuring the absolute width values. Operation of one of the proposed circuits was confirmed by a radiation experiment of alpha particles with a fabricated test chip.

This paper presents a measurement circuit structure for capturing SET pulse-width suppressing pulse-width modulation and within-die process variation effects. For mitigating pulse-width modulation while maintaining area efficiency, the proposed circuit uses massively parallelized short inverter chains as a target circuit. Moreover, for each inverter chain on each die, pulse-width calibration is performed. In measurements, narrow SET pulses ranging 5ps to 215ps were obtained. We confirm that an overestimation of pulse-width may happen when ignoring die-to-die and within-die variation of the measurement circuit. Our evaluation results thus point out that calibration for within-die variation in addition to die-to-die variation of the measurement circuit is indispensable.