AM27C256-120DI
| Parameters | |
|---|---|
| Series | - |
| Package / Case | 32-CDIP (0.600", 15.24mm) |
| Mfr | Rochester Electronics, LLC |
| Mounting Type | Through Hole |
| Operating Temperature | -40°C ~ 85°C (TA) |
| Technology | EPROM - UV |
| Supplier Device Package | 32-CDIP |
| Access Time | 120 ns |
| Memory Size | 256Kbit |
| Memory Type | Non-Volatile |
| Voltage - Supply | 4.5V ~ 5.5V |
| Memory Organization | 32K x 8 |
| Memory Format | EPROM |
| Memory Interface | Parallel |
| Write Cycle Time - Word, Page | - |
| Package | Bulk |
| Product Status | Active |
| Base Product Number | AM27C256 |
| Standard Package | 1 |
| ECCN | EAR99 |
| HTSUS | 8542.32.0061 |
AM27C256-120DI EPROM - UV Memory IC 256Kbit Parallel 120 ns 32-CDIP
The AM27C256-120DI is AMD 256Kbit (32K×8) CMOS UV-erasable EPROM housed in windowed 28-pin ceramic CDIP package, featuring 120ns maximum access time and single 5V operating supply, with 12.5V programming voltage required for data burning. This vintage non-volatile memory supports UV light bulk erasure, adopts Flashrite fast programming algorithm, operates at commercial temperature range of 0°C to 70°C, and provides at least 10-year data retention. It has separate chip enable and output enable pins to avoid bus conflict, widely used for legacy firmware storage in old industrial controllers, test instruments and retro embedded systems.
Key Features
● 256Kbit memory organized as 32768×8 bits with 120ns access speed for legacy CPU read operation.
● Windowed ceramic CDIP-28 package, allowing chip erasure via ultraviolet light for repeated reprogramming.
● Single 5V VCC supply for read operation, 12.5V VPP programming pin for writing firmware data.
● Low power CMOS design with microamp-level standby current and TTL/CMOS compatible I/O signals.
● Independent CE and OE control pins to eliminate bus contention in multi-memory microprocessor systems.
● Flashrite fast programming algorithm with short pulse programming, completing full chip programming quickly.
● Latch-up protection and high noise immunity, JEDEC standard pinout for simple board replacement.
FAQ: Can AM27C256-120DI retain data under sunlight? The window is sensitive to UV; avoid long-term exposure to natural light to prevent accidental data erasure. Use professional UV eraser for chip erasure and strictly follow 12.5V programming voltage specification to prevent chip damage.
Alternative EPROM models
● M27C256B-12F1: STMicroelectronics 32K×8 UV EPROM with 120ns access time, DIP28 pin compatible direct replacement for legacy firmware storage.
● AM27C256-90DI: AMD faster 90ns version of same EPROM series, suitable for systems requiring shorter memory access latency.
● W27C256: EEPROM alternative with electric erase without UV lamp, convenient for rapid firmware update of old hardware.
