Novel Radiation Hardened Pre-Discharge Sense Amplifier for Double Data Rate Magnetic Random Access Memory

The ever-increasing demand for non-volatile memories with high density, low power consumption, and resistance to radiation has led to the emergence of Double Data Rate Magnetic Random Access Memory (DDR-MRAM) as a promising technology. However, the reliability of DDR-MRAM in harsh radiation environments remains a challenge. This paper presents a novel radiation-hardened pre-discharge sense amplifier specifically designed for DDR-MRAM application. The paper investigates the effects of radiation on the unhardened pre-discharge sense amplifier (PDSA) circuit and proposes solutions at both the device and circuit levels. At the circuit level, two distinct circuits have been proposed: one involves the duplication technique (PDSA-D) and the other employs a feedback circuitry (RT-PDSA) to harden sensitive transistors in the PDSA. The proposed radiation tolerant PDSA (RT-PDSA) circuit demonstrates significant improvements in terms of single event upset (SEU) as well as double node upset (DNU) mitigation by considering minimum sensitive nodes layout area separation concept and enhanced compared to unhardened PDSA circuit. The overall performance of the proposed circuit has been analyzed in terms of the figure of merit (FOM), which includes critical charge tolerability, the number of sensitive nodes, recovery time, and area. The proposed RT-PDSA circuit has 11.95 <tex-math notation="LaTeX">×</tex-math> and 8.7 <tex-math notation="LaTeX">×</tex-math> higher FOM compared to the hardened PDSA at the device level, and PDSA-D circuit, respectively. Moreover, the proposed circuit exhibits robustness against process variations, making it a promising solution for enhancing DDR-MRAM's reliability in radiation-intensive environments.