Analysis of SER Improvement by Radiation Hardened Latches

Soft error rate (SER) of various radiation hardened latches is analyzed by simulation. SER is estimated by modeling the variety of current pulses triggered by particle strikes such as neutrons from space or alpha particles using Monte Carlo method. By using proposed method, we show that SER of various latches is accurately analyzed without conducting irradiation experiments. As for the soft error tolerant latches, we use DICE, Path-exclusive, BISER and TMR latches. The DICE and Path-exclusive latches achieve soft error resilience by adopting local redundancy with feedbacks from cross coupled nodes, on the other hand, BISER and TMR latches archive soft error resilience by multiplexing vulnerable normal latches with the help of auxiliary circuit to mask error states. From our simulation results, it is confirmed that Path-exclusive latch is the most favorable radiation hardened latch design with limited delay, area and energy overhead.