Intel AN28F010-120: A 1-Megabit CMOS EPROM for High-Speed Systems

The relentless pursuit of higher performance in computing and embedded systems of the late 1980s and early 1990s demanded memory components that could keep pace with increasingly fast microprocessors. Addressing this critical need, Intel Corporation introduced the AN28F010-120, a high-performance 1-megabit CMOS EPROM that became a cornerstone for developers of high-speed systems.

This device organized as 128K x 8 bits, provided a significant density for its time, enabling the storage of substantial firmware or system BIOS. Its most defining characteristic was its 120ns maximum access time, denoted by the "-120" suffix. This speed was crucial for systems employing high-frequency CPUs without introducing wait states, which would otherwise throttle overall system performance. By allowing the processor to access code at full speed, the AN28F010-120 was instrumental in maximizing the throughput of computing designs.

Fabricated with Intel's advanced CMOS technology, the chip offered substantial advantages over the older NMOS-based EPROMs. These benefits included significantly lower power consumption, both in active and standby modes, which was vital for reducing thermal output and improving system reliability. Furthermore, the CMOS process contributed to the chip's ability to operate reliably at high speeds.

The AN28F010 featured a standard JEDEC-approved pinout, ensuring second-source availability and easy upgradeability from lower-density EPROMs like the 27256 or 27512. Programming was straightforward, utilizing the common intelligent programming algorithms of the era, such as Intel's own Quick-Pulse Programming (QPP), which helped to prevent over-programming and ensure reliable manufacturing. The familiar glass window for ultraviolet erasure allowed for thousands of erase/reprogram cycles, providing flexibility during the product development and debugging phases.

While eventually superseded by Flash memory, which offered in-system electrical erasure, the AN28F010-120 represented the pinnacle of its technology. It delivered a perfect balance of the three key metrics essential for high-performance designs: speed, density, and reliability.

ICGOOODFIND: The Intel AN28F010-120 was a pivotal component in the evolution of high-speed computing, setting a benchmark for performance with its 120ns access time. Its combination of high density, low CMOS power consumption, and industry-standard compatibility made it a preferred and reliable solution for demanding system designs, bridging the gap between older EPROMs and the nascent Flash memory technology.

Keywords: High-Speed EPROM, 120ns Access Time, CMOS Technology, 1-Megabit Memory, Intel Memory Chip