[en] Two lots of SEEQ 28C256 EEPROM were tested for total dose tolerance. Differences between them were found to result in a dependent of the relative superiority and failure doses of the two lots on the test method and the failure criterion. The failure doses were between 6 and 15 krad, and the failure mechanisms were an increase in the standby current and a loss of programmability

[en] The sensitivity of some analog and digital integrated circuits (IC's) to ionizing radiation was tested in order to evaluate their potential usefulness especially in the PROMICS-3 instrument. The PROMICS-3 is a plasma instrument to be flown on the Russian Interball satellites. The radiation tolerance requirement of the auroral Interball satellite is about 45 krad/year inside a shielding of 4 mm Aluminium. The IC's tested were: AD571 A/D- converter, ADDAC80 D/A-converter, LF442A and PM108A operational amplifiers, MPREF0l voltage reference, STC SPXO 6 MHZ oscillator,4N55 optocoupler, MC5lC98 and CY7C164 16k*4 static CMOS RAM. Co-60 was used as the irradiation source. The test methods and results are described in the paper. The RAM-circuits failed between 10 and 20 krad. D/A- and A/D-converters degraded only slightly after 100 krad, but one of the A/D-converters failed functionally at 190 krad. The LF442A began to degrade in the test connection at 100 krad, and PM108A at 30 krad. The output voltage of the voltage reference MPREF01 increased about 20 mV after 100 krad. No change was observed in the output frequency of the STC SPXD oscillator even after 300 krad. The current tansfer ratio of the 4N55 decreased continuously to about 75 % of the initial value after 100 krad

[en] The design of the ERNE experiment of the ESA and NASA collaborative SOHO mission is described. ERNE will investigate the sun by measuring energetic particles. Starting from the design objectives, as determined by the scientific goals of the experiment, and from the adopted basic solutions, the design and structure of the instrument are presented in detail. The fundamental technical aspects encountered in building a space instrument are briefly considered. The methods of implementation of scientifically the most important parts of the instrument, the sensors for measuring energetic particles and the associated electronics, are thoroughly explained. Both hardware and software are examined. The pre-flight calibrations of the instrument are described and the performance of the instrument in space is demonstrated. (orig.)