1 Kbit serial EEPROM in a 2x3 mm package
The Microchip AT93C46DY6-YH-E is a 1 Kbit non-volatile EEPROM organized as 128 x 8 or 64 x 16 bits, accessed through a 3-wire serial interface. The 2 MHz clock frequency sets the read/write throughput ceiling; each write cycle takes 5 ms (word or page). This density tier is typical for storing calibration constants, serial numbers, or a small configuration block in industrial control, telecom, or sensor modules.
The 8-UFDFN with exposed pad (2x3 mm body) saves board area on compact designs; the thermal pad should be stitched to a ground plane with vias to pull heat out of the package during sustained write cycles.
For dual-sourcing or a density upgrade, the AT93C56B-SSHM-B (2 Kbit, same 3-wire interface, SOIC-8) is a functional step-up, though the package differs.