MR25H10 1Mb Serial SPI MRAM FEATURES No write delays Unlimited write endurance Data retention greater than 20 years Automatic data protection on power loss Block write protection Fast, simple SPI interface with up to 40 MHz clock rate 2.7 to 3.6 Volt power supply range DFN Low current sleep mode Industrial temperatures Available in 8-pin DFN or 8-pin DFN Small Flag RoHS-compliant packages Direct replacement for serial EEPROM, Flash, FeRAM AEC-Q100 Grade 1 Option Small Flag DFN INTRODUCTION The MR25H10 is a 1,048,576-bit magnetoresistive random access memory (MRAM) device organized as 131,072 words of 8 bits. The MR25H10 offers serial RoHS EEPROM and serial Flash compatible read/write timing with no write delays and unlimited read/write endurance. Unlike other serial memories, both reads and writes can occur randomly in memory with no delay between writes. The MR25H10 is the ideal memory solution for applications that must store and retrieve data and programs quickly using a small number of I/O pins. The MR25H10 is available in either a 5 mm x 6 mm 8-pin DFN package or a 5 mm x 6 mm 8-pin DFN Small Flag package. Both are compatible with serial EEPROM, Flash, and FeRAM products. The MR25H10 provides highly reliable data storage over a wide range of temperatures. The product is offered with Industrial (-40 to +85 C) and AEC-Q100 Grade 1 (-40C to +125 C) operating temperature range options. CONTENTS 1. DEVICE PIN ASSIGNMENT......................................................................... 2 2. SPI COMMUNICATIONS PROTOCOL...................................................... 4 3. ELECTRICAL SPECIFICATIONS................................................................. 10 4. TIMING SPECIFICATIONS.......................................................................... 12 5. ORDERING INFORMATION....................................................................... 12 6. MECHANICAL DRAWING.......................................................................... 13 7. REVISION HISTORY...................................................................................... 15 How to Reach Us.......................................................................................... 15 Copyright Everspin Technologies 2018 1 MR25H10 Rev. 9.5 3/2018MR25H10 1. DEVICE PIN ASSIGNMENT Overview The MR25H10 is a serial MRAM with memory array logically organized as 128Kx8 using the four pin in- terface of chip select (CS), serial input (SI), serial output (SO) and serial clock (SCK) of the serial peripheral interface (SPI) bus. Serial MRAM implements a subset of commands common to todays SPI EEPROM and Flash components allowing MRAM to replace these components in the same socket and interoperate on a shared SPI bus. Serial MRAM offers superior write speed, unlimited endurance, low standby & operating power, and more reliable data retention compared to available serial memory alternatives. Figure 1.1 Block Diagram Instruction Decode WP Clock Generator CS Control Logic HOLD Write Protect SCK 128KB MRAM ARRAY Instruction Register 17 8 Address Register Counter SO Data I/O Register SI 4 Nonvolatile Status Register System Configuration Single or multiple devices can be connected to the bus as shown in Figure 1.2. Pins SCK, SO and SI are common among devices. Each device requires CS and HOLD pins to be driven separately. Figure 1.2 System Configuration SCK MOSI MISO SO SI SCK SO SI SCK SPI EVERSPIN SPI MRAM 1 EVERSPIN SPI MRAM 2 Micro Controller CS HOLD CS HOLD CS 1 HOLD 1 CS 2 HOLD 2 MOSI = Master Out Slave In MISO = Master In Slave Out Copyright Everspin Technologies 2018 2 MR25H10 Rev. 9.5 3/2018