CNTFET based radiation hardened latch

Abstract

ABSTRACT In this paper, a carbon nanotube field effect transistor (CNTFET) based single event upset (SEU) tolerant latch is proposed. The proposed latch can tolerate the effect of particle strike at any of its storage nodes thus making it completely immune to SEU. Presented work focusses on latch design to mask the single event transient (SET) pulses generated in combinational circuits preceding a latch/register in a digital system. In this work, already existing latches are implemented in CNTFET technology and compared with the proposed latch by running a set of simulations using HSPICE. The impact of single event effects (SEEs) on various CNTFET based latches have been investigated and it is observed that the proposed latch is most efficient in filtering SET pulses. The proposed latch is able to filter SET with a maximum pulse width of 12.3 pS. The proposed latch has also been compared with existing latches on the basis of two comprehensive performance metrics referred to as Ability of SET Filtering (AOSF) and Area-Power-Delay-Pulse Product (APDPP). It is observed that the proposed latch demonstrates best AOSF (that is a measure of SET filtering efficiency) of 93.04% among the latches considered for comparison in this work.