Active 256 Mbit quad-SPI NOR — 133 MHz read clock
The MT25QU256ABA1EW7-0SIT TR is an active-production 256 Mbit NOR flash from Micron's MT25QU family, built for code-shadow and data-logging applications that need non-volatile storage with fast random access. It communicates over a SPI bus with Quad I/O support, clocking reads at up to 133 MHz — enough to feed a Cortex-M4 or RISC-V core executing directly from flash without a separate DRAM cache. Memory is organized as 32M x 8 bits, with page write times of 2.8 ms typical and a word write cycle of 8 ms.
Package and board-fit — 8-WDFN with exposed pad
The exposed pad also provides mechanical stability — important if this flash is the only non-volatile memory on a board that sees vibration.
Supply and temperature — tight rail, industrial range
Operates from 1.7 V to 2.0 V — a narrow supply window that matches 1.8 V logic families but needs a clean rail; a 1.8 V LDO with 200 mV dropout at 100 mA is marginal here because the flash's inrush during a page program can pull the rail below 1.7 V.