Total-dose and single-event effects in the linear control circuitry of DC/DC power converters are examined. Catastrophic failure, induced by error-amplifier total-dose irradiation, is compared for two modes of operation. The use of a more robust restart mechanism to maintain the operation of the converter at a much higher dose level is presented. Single events result in missing pulses at the output of the control circuitry. Hybrid and integrated (SG1525A) pulse width modulators are evaluated to illustrate the missing-pulse results.