32 Kbit I²C EEPROM in a 2x3 mm DFN
The Microchip 24LC32AT-I/MC is a 32 Kbit (4K x 8) serial EEPROM with an I²C interface, clocked at 400 kHz and rated for 900 ns access time. The 8-VFDFN package with exposed pad (2x3 mm DFN) saves board area compared to SOIC alternatives.
I²C bus timing and write-cycle budget
At 400 kHz the I²C bus runs standard fast-mode; the 900 ns access time means the host waits one clock cycle after addressing before data appears. The 5 ms write-cycle time per page (word/page write) sets the upper bound for firmware update loops — a 32-byte page write takes 5 ms, so a full 4 KB array rewrite takes about 640 ms if done page by page. That matters for OTA staging or calibration updates where the system must not stall the main loop.