Critical charge characterization in 6-T SRAMs during read mode

In this work we analyze the effects of radiation-induced transient pulses on 6T SRAM cells operating in read mode. The critical charge of a memory cell during read mode is lower than in hold mode. For 1 to 0 upsets, this reduction reaches a factor x 1.5 for events produced by alpha particles; this factor is even higher for longer induced current pulses. The impact of events propagated through the bit-lines is also analyzed. Results show that it is possible the occurrence of an upset in the sense amplifier producing a wrong output in the readout process without changing the memory cell stored value.