64 Mbit SPI flash — the scorch-mark tells you it's the DataFlash family
The AT45DB641E-SHN-T is a 64 Mbit serial flash from Renesas's DataFlash family, organized as 264 bytes per page across 32K pages. That 264-byte page size is the hallmark of the DataFlash architecture — it uses a dual-SRAM buffer scheme so writes are page-aligned, and a partial-page write triggers an internal read-modify-write cycle that takes 8 µs for the buffer load and 5 ms for the page erase. The SPI interface runs up to 85 MHz, which on a quad-I/O read gives a throughput ceiling around 34 MB/s — enough to shadow a firmware image into RAM or stream data-log buffers without stalling the host controller.
Active lifecycle — no PCN watch needed
Renesas lists the AT45DB641E-SHN-T as Active.
Package and board-fit — 8-SOIC wide-body
The supplier device package is 8-SOIC, and the mounting is surface-mount.
Peer cross-reference — AT45DB641E-SHN2B-T drops in without rewiring
The closest functional sibling is the AT45DB641E-SHN2B-T. The difference is in the ordering code suffix — the SHN2B variant uses a different test-flow revision.