This document describes the distinctive characteristics of the Am27C256 256 Kilobit (32 K x 8-Bit) CMOS EPROM, including fast access time, low power consumption, single +5V power supply, 100% Flashrite™ programming, high noise immunity, etc.
The Am27C256 is a 256‑Kbit ultraviolet‑erasable programmable read‑only memory organized as 32 K × 8 bits. It operates from a single +5 V supply, offers fast 45 ns access, and provides both CMOS and TTL compatible I/O. The device is available in 28‑pin ceramic DIP, 28‑pin plastic DIP, and 32‑pin PLCC packages.
Key features include low power consumption (typical 20 µA standby), latch‑up protection, high noise immunity, and Flashrite™ programming that programs the entire array in about 4 seconds. The EPROM can be erased with UV light (15 W·s/cm² for 15‑20 minutes) and supports various speed options from 45 ns to 250 ns.
| Access time (fastest option) | 45 ns |
|---|---|
| Standby current (CMOS) | 20 µA typical |
| Programming time (Flashrite™) | 4 seconds typical |
| Supply voltage | +5 V (single supply) |
| Package types | 28‑pin ceramic DIP, 28‑pin plastic DIP, 32‑pin PLCC |
Programming the entire EPROM with the Flashrite™ algorithm typically takes about 4 seconds.
The device operates from a single +5 V supply.
It is offered in 28‑pin ceramic DIP, 28‑pin plastic DIP, and 32‑pin PLCC packages.