2Kbit serial EEPROM for parameter storage
The Microchip AT93C56B-SSHM-T is a 2Kbit serial EEPROM organized as 256 x 8 or 128 x 16 bits, accessed through a 3-wire serial interface. It operates from a single 1.7V to 5.5V supply, making it a drop-in fit for 1.8V, 2.5V, 3.3V, or 5V logic domains without an extra regulator. The 2 MHz clock frequency supports read and write cycles up to that rate, with a write cycle time of 5 ms per word or page. This part is suited for storing calibration constants, configuration tables, serial numbers, or small firmware patches in industrial controls, consumer electronics, and telecom modules where non-volatile retention is needed across power cycles.
The wide supply tolerance—1.7V minimum—means it will hold data and remain writable even during a brown-out on a 1.8V rail, a useful margin for battery-powered designs.
Memory organization and write timing
The 5 ms write cycle time per word or page is typical for this class of EEPROM; a firmware engineer should budget for the write delay in the main loop or use a status-polling routine if available. At 2 MHz, a 16-bit read takes about 8 µs plus overhead, fast enough for most configuration reads at power-up.
ROHS3 compliance is confirmed. For a BOM line requiring a 2Kbit 3-wire serial EEPROM in SOIC-8, the AT93C56B-SSHM-T is a current, low-risk choice.