Total ionization dose and transient dose rate effects of a Toggle magnetoresistive random access memory

BackgroundMagnetoresistive random access memory (MRAM) has the advantages of non-volatility, fast speed, low power consumption, high endurance, and long data retention, making it a potential candidate for application in aerospace electronic systems.PurposeThis study aims to examine the total ionization dose (TID) and transient dose rate (TDR) effects of a Toggle MRAM.MethodsA remote on-line test system was designed for in-situ measurement of the radiation effect of the MRAM. Five test modes were designed for experimental test, including static mode, static power-on mode, dynamic read-write mode, dynamic write mode, and dynamic read mode. The TID and TDR response of MRAM were studied experimentally in five working modes.ResultsExperimental results show that the early response of the MRAMs is an increase of the supply current during TID experiment, and bit errors occur at a total dose of 30 krad(Si). Neither data nor function errors are observed in static power-on mode and dynamic read mode during the TDR experiment, whereas data write failure occurs in dynamic write mode. Reason for the write failure may be a fluctuation in the power supply caused by the global photocurrent of the circuit which triggers the write protection of the device and hinders the following data writing process.ConclusionsResults of this study indicate that MRAM exhibits malfunctions under total dose and transient ionizing radiation environments. The radiation sensitive and vulnerable part of the MRAM is its peripheral circuits.