关键词: 自旋转移力矩随机磁存储器, 磁隧道结, 宽温区, 温度自适应, 写电压产生电路

Abstract: Spin transfer torque magnetic random access memory (STT-MRAM) is a new type of non-volatile memory with a wide range of applications in various industries. STT-MRAM uses magnetic tunnel junction (MTJ) devices to store information. The write voltage usually has zero temperature coefficient, but the critical flip-flop voltage of MTJ has a negative temperature characteristic, so the difference between the write voltage and the critical flip-flop voltage is large at high temperature, which affects the lifetime of the device, and at low temperature, the write voltage is close to, or may even be lower than the critical flip-flop voltage, which makes it difficult to write. Aiming at the negative temperature characteristic of the critical flip-flop voltage of MTJ, a wide temperature adaptive write voltage generator circuit is designed to provide stable write voltage for MTJ at -40-125 ℃, to realize the normal writing of data in wide temperature range, especially at low temperature, and to improve the lifetime of the device at high temperature. After post-simulation verification, the MTJ can be successfully written in the temperature range of -40-125 ℃, and the difference between the write voltage and the critical flip-flop voltage is about 100 mV.

Key words: spin transfer torque magnetic random access memory, magnetic tunnel junction, wide temperature, temperature adaptive, write voltage generation circuit