The MB81256-80 is a 262,144-word by 1-bit Dynamic Random Access Memory (DRAM) manufactured by Fujitsu. It's designed for high-density memory applications requiring fast access times.

Applications

• Personal computers: Used as main memory in older PC systems.
• Workstations: Employed in workstation environments requiring significant memory capacity.
• Graphics cards: Integrated into graphics cards for frame buffer memory.
• Printers: Used as buffer memory in printing devices.
• Industrial control systems: Utilized in industrial automation equipment for data storage.

Features

• Organization: 262,144 words x 1 bit.
• Access Time: 80ns access time, enabling rapid data retrieval.
• Refresh: Requires periodic refresh cycles to maintain data integrity.
• Power Consumption: Operates on a single +5V power supply, minimizing power requirements.
• Package: Typically available in a DIP (Dual In-line Package) for easy integration.

Benefits

• High Density: Provides a large amount of memory in a single chip.
• Fast Access: 80ns access time allows for quick data access, improving system performance.
• Cost-Effective: Offered a cost-effective solution for memory needs in its era.
• Wide Availability: Was a widely used and readily available memory component.
• Ease of Integration: Standard DIP packaging simplifies integration into existing systems.

Additional Details

The MB81256-80 DRAM uses multiplexed address inputs to reduce the number of address pins required. It features a sense amplifier that amplifies the small signals stored in the memory cells. The refresh operation is crucial for maintaining the data stored in the DRAM cells, which lose their charge over time. The operating temperature range is typically between 0°C and 70°C. This memory chip was instrumental in the development of more powerful and efficient computing systems.