2 Mbit serial flash with a wide voltage range
The Adesto AT45DB021E-MHN-Y is a 2 Mbit SPI serial flash memory built for designs that need non-volatile storage with a simple 4-wire interface. It clocks at 70 MHz over SPI, which gives you a read throughput around 8 MB/s — enough for code shadowing, configuration tables, or small data logs. The supply range from 1.65 V to 3.6 V means it plays nicely on both 1.8 V and 3.3 V rails without a level translator, a real BOM simplifier in mixed-voltage systems. Internally the array is organized as 264 bytes per page across 1024 pages, a classic DataFlash page layout that suits small-block reads and writes. Page write time is 3 ms, and a single byte or word can be written in 8 µs — handy for updating a calibration constant without erasing the whole page.
Package and footprint — what to watch
On a two-layer board, stitch at least four vias from the pad to a ground plane pour; on four-layer, a solid via array under the pad keeps junction temperature under control during back-to-back page writes. The part ships in a Tray — if your pick-and-place line feeds from tape, the -T suffix variant (AT45DB021E-MHN-T) is the reeled version with identical silicon.
For dual-sourcing flexibility, the same die is available in a wider SOIC package (AT45DB021E-SSHN-B in tube, AT45DB021E-SSHN-T on tape) — same 2 Mbit, same 70 MHz SPI, same temperature grade, different footprint.