ASIC waveform receiver with improved environmental tolerance for probing space plasma waves in environments with high radiation and wide temperature variation

Abstract

Plasma-wave observations are conducted under conditions of high radiation and wide temperature variation. The electrical characteristics of plasma-wave instruments should therefore be insensitive to these environmental factors. We have developed a new application-specific integrated circuit (ASIC) waveform receiver with a radhard [radiation-hardened] amplifier and a temperature-compensation circuit. The environmental tolerance of the conventional ASIC receiver is unsuitable for probing plasma waves in the range 1 Hz to 10 kHz in harsh space environments. Its weak radiation tolerance under 350 krad results in radiation-induced degradation in noise performance, such that weak plasma waves are lost in the noise floor. With an ambient temperature change of −40° C to +100° C, the gain response of the conventional ASIC receiver varies by more than ±1.0 dB, preventing accurate measurement of plasma waves around the cutoff frequency of 10 kHz. Our new ASIC receiver operates at a total dose rate of 350 krad without degradation in noise performance. Moreover, the temperature dependence of the gain response from −60° C to +100° C dramatically improved by ±0.05 dB due to the addition of a compensation circuit. Our new ASIC receiver can contribute to the measurement of plasma waves in challenging environmental conditions to further the understanding of magnetospheric dynamics.