The MR25H256/MR25H256A is a serial MRAM, logically organized into 32Kx8 memory arrays using the four-pin interfaces of the Serial Peripheral Interface (SPI) bus for chip selection (CS), Serial input (SI), Serial output (SO), and Serial clock (SCK). 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 socket and interoperate on the shared SPI bus. Serial MRAM offers superior write speed, unlimited battery life, low standby and running power, and more reliable data retention compared to available serial memory alternatives.
Block Diagram
Single or multiple devices can be connected to the bus, as shown in Figure 2. Pins SCK, SO, and SI are common devices. Each device requires CS and HOLD pins to be driven separately.
System configuration