Characterization of LDO Induced Increment of SEE Sensitivity for 22-nm FDSOI SRAM

The radiation sensitivity of the Static Random-Access Memory (SRAM) device depends on the basic memory cell and peripheral circuits, and the influence of peripheral circuits is difficult to measure and classify, especially for the internal low dropout regulator (LDO) modules. In this paper, the LDO with radiation-tolerant bipolar bandgap was designed and fabricated to provide power supply for Fully Depleted Silicon on Insulator (FDSOI) SRAM test chips. The LDO induced Single Event Effects (SEE) for SRAM devices were investigated by pulsed laser and heavy ion irradiation tests. The simulation and irradiation results show that the hardened LDO has high SEE tolerance, while a few upset errors for memory units were induced by the transient turbulence of the internal LDO in test chips. The characterization results of LDOs provide specific insights into radiation sensitivity and impacts on the whole chips, and contribute to the full evaluation of high-reliable circuits and systems for space applications.