MX25Ux/MX66Ux 1.8V CMOS OctaBus™ NOR Flash Macronix MX25UM, MX25UW, MX66UM, and MX66UW 1.8V CMOS OctaBus™ NOR Flash are extreme speed memory products built on a Serial Peripheral Interface (SPI) and command protocol, providing extendable I/O capability. These components incorporate flash and RAM into the same data I/O bus, reducing the pin count to twelve. These NOR Flash devices are an ideal solution for Over-the-Air (OTA) update applications, which are becoming more prevalent within automotive cockpit solutions.