The X28HC256S-90 is a high-performance, 256K-bit (32K x 8) parallel EEPROM (Electrically Erasable Programmable Read-Only Memory) manufactured by Xicor Inc. (now part of Intersil/Renesas). It is designed for applications requiring non-volatile memory storage with fast access times and high endurance. The '90' in the part number indicates an access time of 90 nanoseconds.

Applications

• Embedded systems
• Industrial control equipment
• Instrumentation
• Data logging
• Program storage for microcontrollers
• BIOS storage

Features

• 256K-bit (32K x 8) EEPROM
• Fast access time: 90 ns
• Low power CMOS technology
• Automatic page write operation
• Self-timed write cycle
• Data polling for end-of-write detection
• JEDEC standard pinout
• Available in DIP and SOIC packages
• High endurance: 100,000 write cycles per byte
• Data retention: 10 years

Benefits

• Fast Access Time: The 90 ns access time ensures quick data retrieval, essential for performance-critical applications.
• Non-Volatile Memory: Retains data even when power is removed, providing reliable storage for program code and configuration settings.
• High Endurance: With 100,000 write cycles per byte, the device is suitable for applications involving frequent data updates.
• Easy Programming: Simple programming interface allows for easy data storage and retrieval.
• Low Power Consumption: CMOS technology minimizes power consumption, making it suitable for battery-powered applications.
• Data Polling: Data polling feature allows for efficient write cycle management.
• JEDEC Standard Pinout: Simplifies integration into existing systems.

The X28HC256S-90 utilizes an automatic page write operation, which simplifies the write process and reduces programming time. The self-timed write cycle ensures accurate data storage, and the data polling feature allows the host system to detect the end of the write cycle without relying on timing delays. The device is available in both DIP (Dual In-line Package) and SOIC (Small Outline Integrated Circuit) packages for flexible integration into various PCB layouts. Its high endurance and data retention characteristics make it a reliable solution for long-term data storage in a wide range of applications. It typically operates on a 5V power supply and is designed to be compatible with standard microcontroller interfaces.