64 Mbit NOR Flash for automotive and industrial — what the specs mean
Quad I/O at 108 MHz — what it buys you
The SPI Quad I/O interface uses four data lines instead of one, quadrupling the theoretical throughput compared to standard SPI at the same clock. At 108 MHz, the raw bit rate reaches 54 MB/s in Quad I/O fast-read mode. That is enough to feed a 200+ MHz Cortex-M core with code from Flash without stalling, provided the MCU's Quad SPI controller and cache are configured correctly. The 3 ms page write time is typical for NOR; if your application does frequent parameter updates, budget for sector erase overhead (64 KB sectors).
For a production ECU or ADAS module, that qualification is often a gate requirement. The 16-SOIC (300 mil body) package is a common footprint, but verify the PCB land pattern against your assembly house's capability for the 1.27 mm pitch.