The NMC27C256QE-250 is a 256K (32K x 8) UV Erasable PROM (EPROM) manufactured by National Semiconductor (now part of Texas Instruments). It is a non-volatile memory device that can be electrically programmed and erased using ultraviolet light. The -250 suffix indicates an access time of 250 nanoseconds. This EPROM is suitable for storing firmware, boot code, and other data that needs to be retained when power is removed.

Applications:

• Firmware storage in embedded systems
• Boot code storage in microcontrollers
• Program storage for programmable logic devices (PLDs)
• Data storage in industrial control systems
• Storing lookup tables

Features:

• 256K (32K x 8) memory organization
• Fast access time: 250 ns
• UV erasable
• Single 5V power supply
• TTL compatible inputs and outputs

Benefits:

• Non-volatile memory: Retains data even when power is removed.
• Reprogrammable: Can be erased and reprogrammed using UV light, allowing for firmware updates and code revisions.
• Fast access time: Enables quick retrieval of stored data.
• Easy to interface: TTL compatible inputs and outputs simplify integration with other logic devices.
• Wide operating temperature range: Suitable for use in harsh environments.

Technical Specifications:

The NMC27C256QE-250 requires a 5V power supply for operation. The programming voltage for writing data into the EPROM is typically around 12.5V. Erasing is performed by exposing the device to UV light with a wavelength of 2537 Angstroms for a specified duration. Refer to the datasheet for detailed programming and erasing procedures, timing diagrams, and electrical characteristics.