RAM History


(2048x8 bit Core Memory)


The Early Computer Memory

Since the ENIAC -- the first computer to be used commercially, went into service in 1945, there have been only three major memory formats.

In 1945, the ENIAC computer used thousends of vacuum tubes and had a memory of mercury and nickel wire delay lines. Between 1945 and 1954, delay lines, William tubes and magnetic drums was used as memory devices.

In 1952 at MIT, Jay Forrester invented the Core Memory. A core was a small ring of ferrite, a ferromagnetic ceramic material that could be magnetized in either of two directions. This unique feature of core enabled it to hold a bit of information, either a 1 or 0, depending on the direction of the magnetic charge. Core memory was used in about 95% of all computers by 1976.

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 (Closeup of Ferrite Cores)

Closeup of Ferrite Cores

In 1974, transistor (semiconductor) memory had become economical and the move to this type of memory began . Transistors led to integrated chips, wich led to today's very highly integrated technology.
Today a typical memory contains 128 or 256 million bytes (8 bits) of information.

The Birth Of The Semiconductors

In 1968 a small company called Intel was startet and it's charter was to design, manufacture and market semiconductor memory components incorperating large scale integrated (LSI) technology. The company saw an untapped market in the replacement of computer core memories by producing low-cost, standardized circuits in high volume. Initial efforts were directed at bipolar and MOS memories.
The company's first successful product was the 3101 Shottky bipolar memory, a 64-bit high-speed static random access memory (RAM), introduced in 1969.

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 (Early 3101 chip)

Early Intel 3101 chip

Bipolar memories was not new, but Intel adopted an innovation, Shottky bipolar technology.




Later in 1969 Intel also introduced the 1101, a 256-bit static RAM. This was the world's first high-volume MOS semiconductor memory, and the first use of MOS silicone gate technology.

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(Early 1101 chip)

Early Intel 1101 chip

Although the 1101 was too complex and too small to achive broad market acceptans and not capable of penetrating the core market, its basic MOS process was applied to shift registers (a simple form of serial memory).

In the 1970-1971 Intel was working on the 1102 and 1103, two designs for a 1K dynamic RAM using three transistors per memory cell. Intel and Honneywell was partners in the developement of the 1102. As it turned out, the 1102 never made it to the market.

1103 The Core Killer

The introduction of the 1103, the worlds first 1K dynamic RAM, was a turning point in the history of integrated circuit: for the first time significant amount of information could be stored on a single chip. It began to replace core memories and became an industry standard. In 1972 it was the largest selling semiconductor in the world.

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(1103 chip)

Intel 1103 chip

The 1103, by todays standards was a primitive device. It was slow, difficult to make and test, and tuochy to operate. But it proved that semiconductor memories were not only viable, but were a vast improvement over core memories, and it greatly increased the power of computers as they then existed.

The Future Of Computer Memory

A thought about the future of computer memory -- the first era lasted roughly 10 years, the second 20 years. We are now at 30 years of semiconductor memory. Whats next? Will Terabytes of information be stored in suger cube sized chrystals? Will neural networks contain trillions of molecules of bits?