The principal obstacle to greater utilization of piezoelectric actuators in aerospace applications is the extreme inefficiency and heat rejection requirements of the driving electronics. The purpose of this investigation is to take a critical look at how amplifiers for piezoelectric systems are designed and to look for potential areas for improvement. A dimensional analysis of a piezoelectric actuator is performed that indicates that power consumption in an unloaded actuator is extremely low, placing the blame for the exorbitant power demands squarely on the driving electronics. Several strategies for power savings in piezoelectric driving electronics are presented including pulse width modulation, discrete charge control, and a hybrid charge-recovery strategy.

We present experimental results on single-event-induced breakdown in sub-5-nm plasma-enhanced SiO 2 , nitrided SiO 2 , Al 2 O 3 , HfO 2 , and Zr 0 4 Si 1 6 O 4 dielectrics typical of current and future-generation commercial gate oxides. These advanced oxides are found to be quite resistant to ion-induced breakdown. Radiation-induced soft breakdown was observed in some films with 342 MeV Au (LET = 80 MeV/mg/cm 2) but not 340 MeV I (LET = 60 MeV/mg/cm 2). The critical voltage to hard breakdown was found to scale with the square root of the physical oxide thickness, not with the energy stored on the gate capacitance. Alternative dielectrics with equivalent oxide thickness substantially below their physical thickness were found to exhibit significantly higher voltage to hard breakdown than SiO 2 counterparts. All of the samples reached ion-induced hard breakdown at applied voltages well above typical operating power-supply voltages; these findings bode well for the use of advanced commercial integrated circuits in space systems.

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Abstract--Generally good agreement was obtained between the single-event output voltage transient waveforms obtained by exposing individual circuit elements of a bipolar comparator and operational amplifier to an ion microbeam, a pulsed laser beam, and circuit simulations using SPICE. The agreement was achieved by adjusting the amounts of charge deposited by the laser or injected in the SPICE simulations. The implications for radiation hardness assurance are discussed.

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