The M87C257 is a high-speed 262,144-bit UV erasable and electrically programmable EPROM. It incorporates latches for all address inputs to minimize chip count, reduce cost, and simplify the design of multiplexed bus systems. It offers fast access time, low power consumption, programming voltage of 12.75V, electronic signature for automated programming, and programming times of around 3 seconds (using the PRESTO II algorithm).
The M87C257 is a 262,144‑bit UV‑erasable and electrically programmable EPROM that incorporates address latches to reduce chip count and simplify multiplexed bus designs. It is offered in a windowed ceramic DIP package and a plastic PLCC package for applications requiring UV erasure or one‑time programming.
The document provides electrical characteristics, timing parameters, programming procedures, electronic signature mode, and recommended handling and erasure methods, along with mechanical dimensions for both package types.
| Fast Access Time | 45 ns |
|---|---|
| Active Current | 30 mA |
| Standby Current | 100 µA |
| Supply Voltage (VCC) | –2 V to 7 V |
| Programming Voltage (VPP) | –2 V to 14 V |
| Ambient Operating Temperature | –40 °C to 125 °C |
| Storage Temperature | –65 °C to 150 °C |
The standby current is 100 µA.
Erasure is performed by exposing the device to short‑wave ultraviolet light (≈2537 Å) for about 15 to 20 minutes.