64 Kbit serial EEPROM in PDIP-8 — I²C bus, wide supply range
The M24C64-WBN6P is a 64 Kbit serial EEPROM organized as 8K x 8 bits, communicating over the I²C bus at up to 1 MHz clock frequency. Housed in an 8-pin PDIP (0.300-inch, 7.62 mm pitch) through-hole package, this part fits sockets and solder-in applications where board rework or prototyping access matters — the DIP body is still common in industrial control cards, test fixtures, and retrofit designs that avoid SMT.
Timing and write-cycle budget
Read access time is 450 ns — this is the time from the I²C slave address acknowledge to the first data byte appearing on SDA. For a 1 MHz bus (1 µs bit period), the access fits within one clock cycle, so the bus master does not need to insert wait states between the address and the read data. A firmware update writing 64 bytes per page across the full 64 Kbit array takes roughly 640 ms of bus time for the write cycles alone, not counting the address overhead. Budget this into the field-update window — the part does not acknowledge the I²C master during the internal write cycle.
STMicroelectronics has marked the M24C64-WBN6P as Obsolete. No pin-compatible direct replacement is documented by ST; a functional equivalent would require verifying the I²C slave address, page size, and write-cycle timing against the replacement device.