The DM87S185N is a high-speed, 16,384-bit (2048 x 8) bipolar programmable read-only memory (PROM) manufactured by National Semiconductor, now part of Texas Instruments (TI). This PROM is designed for use in applications requiring fast access times and reliable data storage.

Applications

• Microprogram storage
• Lookup tables
• Character generators
• Code converters
• High-speed data storage

Features

• Organized as 2048 words x 8 bits
• Typical access time of 45 ns
• Tri-state outputs
• Low input current
• PNP inputs for reduced loading
• Available in a 24-pin DIP package
• High-reliability

Benefits

• Provides fast access to stored data
• Offers a large storage capacity for microprograms and lookup tables
• Enables easy memory expansion with tri-state outputs
• Reduces system power consumption with low input current
• Simplifies interfacing with other components due to PNP inputs
• Facilitates easy installation and replacement with standard DIP package
• Ensures reliable performance in demanding environments

Additional Details

The DM87S185N is a bipolar PROM, which means it uses bipolar junction transistors (BJTs) for its memory cells. This technology provides faster switching speeds compared to MOS-based PROMs, making it suitable for applications where speed is critical. The PROM is programmed by selectively blowing fuses within the memory array. Once programmed, the data is permanently stored and cannot be erased. The tri-state outputs allow multiple PROMs to be connected in parallel to increase the memory capacity of the system. The low input current minimizes the load on the driving circuits, while the PNP inputs further simplify interfacing. The DM87S185N is available in a 24-pin DIP package, making it easy to install and replace in standard circuit boards.

The DM87S185N PROM from National Semiconductor (TI) is a reliable and high-speed memory solution for a variety of applications. Its fast access time, large storage capacity, and easy interfacing make it a popular choice for designers of embedded systems and digital logic circuits.