4 Kbit I²C EEPROM in a 2x3 mm UDFN
The Microchip AT24C04D-MAHM-E is a 4 Kbit serial EEPROM organized as 512 x 8 bits, accessed through an I²C interface running up to 1 MHz. The 8-UDFN package with exposed pad (2x3 mm) keeps the footprint small while the pad aids thermal and ground connection.
1 MHz I²C and 4.5 µs access — bus timing fit
The 1 MHz clock supports Fast-mode Plus I²C. The 4.5 µs access time is the random-read latency from address to first data byte.
Supply range and write-cycle budget
Write-cycle time is 5 ms per word or page; a page write loads up to 16 bytes in one I²C transaction, then the internal timer handles the programming. For a 4 Kbit device, rewriting the entire array takes roughly 1.3 seconds worst-case — factor that into any field-update routine.
The 8-UDFN (2x3 mm) with exposed pad requires a solder-paste stencil opening for the center pad; the pad should be tied to ground or left floating per the datasheet recommendation.
Microchip lists the AT24C04D-MAHM-E as Active. For production planning, the part is in current manufacture and can be specified into new BOMs without near-term obsolescence risk. The base product number AT24C04 covers multiple package and temperature variants, so if the 8-UDFN footprint is not locked, a pin-compatible SOIC or TSSOP sibling exists within the same family.