“Persistent memory” usually refers to a high-performance, byte-addressable, non-volatile memory device that resides on a memory bus. Both MRAM (magnetic read-only memory) and FRAM (ferroelectric RAM) claim similar performance advantages: low voltage operation, long life, and very high speeds. They achieve these goals in different ways, although in each case, there are innovative materials technologies behind the performance breakthroughs. The pioneering MRAM stores bits of data as changes in the resistance of a storage cell, which are created by exposing some special material to a magnetic field. FRAM is very different from MRAM in that it stores bits as fixed potentials (voltages) in ferroelectric materials. A Serial MRAM chip MR25H256ACDF that can replace FRAM is described below.

MR25H256ACDF is a serial MRAM, its memory array logic organization is 32KX8, using serial peripheral interface chip selection (CS), serial input (SI), serial output (SO) and serial clock (SCK) four pin interface (SPI) bus. Serial MRAM implements a subset of commands common to today’s SPI EEPROM and flash components, allowing MRAM to replace these components in the same slot and interoperate on a shared SPI bus. Serial MRAM offers superior write speed, unlimited durability, low standby and running power, and more reliable data retention compared to available serial memory alternatives.

Features • No write delay • Unlimited write durability • Data retention over 20 years • Automatic data protection in case of power failure • Block write protection • Fast and simple SPI interface Clock rates up to 40MHz • Power range from 2.7 to 3.6 volts • Low current sleeping mode • Industrial and automotive level 1 and 3 temperatures • Available in 8-DFN Small Flag RoHS compliance packages. • Direct replacement of serial EEPROM, flash memory, and FERAM • Industrial and AEC-Q1001 and Level 3 options • Humidity sensitivity MSL-3

EverSpin Technologies, Inc is a leader in the design, manufacture and commercial transportation of discrete and embedded reluctance RAM (MRAM) and spin transfer torque MRAM (STT-MRAM) markets and applications for data persistence and applications. Integrity, low latency, and security are critical. With more than 120 million MRAM and STT-MRAM products deployed in the data center, cloud storage, energy, industrial, automotive, and transportation markets, EverSpin has laid the strongest and fastest growing base for MRAM users.