AT24C128B is a 128K (16,384x8) serial electrically erasable and programmable read-only memory (EEPROM) with 1.8V (VCC = 1.8V to 5.5V) and 2.5V (VCC = 2.5V to 5.5V) compatibility. The device is available in 8-lead JEDEC PDIP, 8-lead JEDEC SOIC, 8-lead Ultra Thin Mini MAP, 8-lead Ultra Lead Frame Land Grid Array (ULA), 8-lead TSSOP and 8-ball dBGA2 packages.
The AT24C128B is a 128‑Kbit (16,384 × 8) two‑wire serial EEPROM offered in multiple 8‑lead packages such as PDIP, SOIC, TSSOP and BGA. It operates from 1.8 V to 5.5 V, supports up to eight devices on a common bus, and is suited for industrial and commercial low‑power applications. The device includes a write‑protect pin, 64‑byte page write mode, and a self‑timed write cycle.
The datasheet details absolute maximum ratings, DC and AC electrical characteristics, pin functions, memory organization (256 pages of 64 bytes), device addressing, standby mode, and software reset procedures. It also provides revision history and Atmel contact information.
| Supply Voltage | 1.8 V – 5.5 V |
|---|---|
| Write Cycle Time | 5 ms (typ) |
| Endurance | 1 000 000 write cycles |
| Data Retention | 40 years |
| Maximum Clock Frequency | 1 MHz (5.5 V, 2.5 V) / 400 kHz (1.8 V) |
Up to eight devices can share a common two‑wire bus.
When WP is tied to GND normal writes are allowed; when tied to VCC all write operations are inhibited.
The typical write‑cycle time is 5 ms.
The device is rated for one million write cycles.