Spin-transfer Torque MRAM Technology

Everspin’s Spin-transfer Torque (STT) MRAM technology uses the spin-transfer torque property, which is the manipulation of the spin of electrons with a polarizing current, to establish the desired magnetic state of a magnetic tunnel junction (MTJ). 

STT-MRAM delivers a significant reduction in switching energy compared to our Toggle MRAM. It is highly scalable, enabling higher density memory products. Everspin STT-MRAM uses a perpendicular MTJ with high perpendicular magnetic anisotropy, providing long data retention, small cell size, greater density, high endurance, and low power. In a write operation, the direction of the polarizing current passing through the MTJ will determine the magnetic state of the free layer. When parallel to the fixed layer, the MTJ is in a low resistance state and when anti-parallel, it is in a high resistance state, effectively providing an equivalent of a bit cell in a logic one or zero state.

 

 Everspin has developed STT-MRAM products that are optimized for different memory workloads and use cases. For data center and enterprise storage applications, we offer a 1Gb density device that has a DDR4 like interface and operates like a persistent DRAM. 

We have also advanced the STT technology to operate over a wider temperature range with extended write endurance and data retention to provide products for Industrial IoT and broader embedded systems applications. These products employ the new JEDEC standard xSPI interface to offer unprecedented bandwidth for reads and writes in industry standard packages with low pin count, low latency, and high speed data transfers. 

 

Spin-transfer Torque Products

ST-DDR4 for Data Center

xSPI for Industrial IoT and Embedded Systems

Everspin Patents