The 24AA256/24LC256/24FC256 is a 32K x 8 (256 Kbit) Serial Electrically Erasable PROM, capable of operation across a broad voltage range (1.8V to 5.5V) developed by Microchip Technology Inc. for advanced, low-power applications such as personal communications or data acquisition. It has a page write capability of up to 64 bytes of data. It is capable of both random and sequential reads up to the 256K boundary. Functional address lines allow up to eight devices on the same bus, for up to 2 Mbit address space. It is available in the standard 8-pin plastic DIP, SOIC, TSSOP, MSOP and DFN packages.
The 24AA256, 24LC256 and 24FC256 devices are 32‑K × 8 (256‑Kbit) CMOS serial EEPROMs that operate from 1.8 V to 5.5 V. They support low‑power applications, offer a 64‑byte page‑write mode and can be cascaded for up to eight devices on a single I²C‑compatible bus.
The document lists electrical characteristics such as maximum write current (3 mA at 5.5 V), maximum read current (400 µA at 5.5 V), standby current (100 nA typical at 5.5 V), endurance (1 000 000 erase/write cycles), and data retention (>200 years). Pin functions, bus protocol, device addressing and timing diagrams are also described.
| Operating Voltage Range | 1.8 V to 5.5 V |
|---|---|
| Maximum Write Current | 3 mA at 5.5 V |
| Maximum Read Current | 400 µA at 5.5 V |
| Standby Current | 100 nA typical at 5.5 V |
| Endurance | 1 000 000 erase/write cycles |
| Data Retention | > 200 years |
| Package Types | 8‑pin PDIP, SOIC, TSSOP, MSOP, DFN |
The 24AA256 supports a maximum clock frequency of 400 kHz.
Up to eight devices can be cascaded on the bus (two for the MSOP package).
When WP is tied to Vss, write operations are enabled; when tied to Vcc, writes are inhibited while reads remain allowed.
Typical standby current is 100 nA at a supply voltage of 5.5 V.