16 Mbit SPI flash with Quad I/O — what it is and where it fits
The AT45DQ161-SHF-T is a 16 Mbit serial flash memory from Microchip Technology (formerly Adesto) built on a non-volatile FLASH process. It communicates over an SPI bus with Quad I/O support, meaning the same four data lines used for address and command can also deliver data at four bits per clock cycle — a real throughput advantage over basic SPI when the controller supports it. The memory is organized as 4096 pages of 528 bytes each, which maps well to code shadowing, data logging, or configuration storage in embedded systems. It operates from a 2.3 V to 3.6 V supply and is rated over the industrial temperature range of -40°C to 105°C, so it can sit on a motor-drive control board or an outdoor telecom module without thermal concern.
Package and mounting — 8-SOIC wide-body
The part comes in an 8-pin SOIC wide-body package (0.209-inch body width, 5.30 mm), surface-mount only. The wide-body SOIC is a common footprint shared with many serial EEPROMs and flash parts.
Lifecycle and compliance — active, no obsolescence risk
It is ROHS3 compliant, so it meets the current EU restriction requirements without an exemption. For a BOM line that needs a reliable serial flash for the next several years, this part is a safe selection — no last-time-buy scramble, no substitute qualification required.