64 Kbit I²C EEPROM in a wafer-level chip-scale package
It operates at a clock frequency up to 1 MHz and delivers a 450 ns access time, making it a fit for parameter storage, calibration data, and firmware configuration in space-constrained designs.
WLCSP package — board-space trade-offs
This variant comes in a 5-bump WLCSP measuring 0.96 x 1.07 mm (supplier device package 5-WLCSP). That footprint is the smallest in the M24C64 family, roughly a third the area of an SO-8. Rework is possible with hot air if the board has a solder mask defined pad and you keep the nozzle temperature under 300°C — lift the part, not the pad. The tape-and-reel shipping format (Cut Tape also available) feeds directly into pick-and-place for high-volume assembly.
Supply voltage and bus compatibility
The I²C interface is open-drain, so the pull-up resistors set the bus voltage — match them to the fastest device on the bus. At 1 MHz, the bus capacitance budget tightens; keep total load under 400 pF to maintain rise-time specs.
Write cycle time and endurance planning
The write cycle time for a word or page is 5 ms. The 64 Kbit array is organized as 8K x 8, so each page write can update up to 8 bytes in one cycle. For frequent parameter updates, consider wear-leveling in software if the application requires more than a few hundred thousand writes to the same address.
The base product number M24C64 spans multiple package options, so if your board later needs a larger footprint (SO-8, TSSOP-8), the same die in a different package is available without requalifying the memory controller interface.