Title :
Single event mirroring and DRAM sense amplifier designs for improved single-event-upset performance
Author :
Gulati, Kush ; Massengill, Lloyd W. ; Agrawal, Ghasi R.
Author_Institution :
Dept. of Electr. and Comput. Eng., Vanderbilt Univ., Nashville, TN, USA
Abstract :
This paper proposes and investigates schemes for hardening the conventional CMOS cross-coupled DRAM sense amplifier to single event upset (SEU). These schemes, adapted from existing SRAM hardening techniques, are intended to harden the dynamic random access memory to bitline-mode errors during the sensing period. Simulation results indicate that a 9 k/spl Omega/ L-resistor hardening scheme provides greater than 24-fold improvement in critical charge over a significant part of the sensing period. Also proposed is a novel single event (SE) mirroring concept for SEU hardening of DRAMs. This concept has been implemented for hardening the bitlines to hits on diffusion regions connected to the lines during the highly susceptible high-impedance state of the bitlines. It is shown to result in over 26-fold improvement in the level of critical charge using a 2pF dynamic capacitive coupling.<>
Keywords :
CMOS memory circuits; DRAM chips; integrated circuit testing; radiation hardening (electronics); space vehicle electronics; 2 pF; 9 kohm; CMOS cross-coupled DRAM; DRAM sense amplifier designs; L-resistor hardening scheme; SRAM hardening techniques; bitline-mode errors; dynamic capacitive coupling; high-impedance state; sensing period; single event mirroring; single-event-upset performance; Alpha particles; Circuits; Computer errors; DRAM chips; Degradation; Impedance; Packaging; Random access memory; Single event upset; Space technology;
Journal_Title :
Nuclear Science, IEEE Transactions on