Intel 1103

Intel 1103. The Intel 1103 is a 1-kilobit dynamic random-access memory (DRAM) integrated circuit, widely recognized as the first commercially available DRAM chip. Introduced by Intel Corporation in October 1970, it revolutionized computer memory by offering a denser and more cost-effective alternative to magnetic-core memory, the dominant technology of the era. Its success established DRAM as the standard for main memory in computers, catalyzing the growth of the semiconductor memory industry and enabling the development of the modern microprocessor.

History and development

The development of the Intel 1103 was driven by the need for a cheaper, higher-density memory solution for the burgeoning minicomputer market. The project was led by a team at Intel that included key figures like Joel Karp and William Regitz, building upon earlier experimental work such as the Intel 1102. A significant breakthrough was the adoption of a three-transistor memory cell design, which was more manufacturable with the semiconductor device fabrication processes of the early 1970s. The chip's development was closely tied to the needs of early customers like Honeywell and Burroughs Corporation, whose systems demanded reliable, solid-state memory. Its commercial release in late 1970 followed intense testing and refinement to overcome initial yield and reliability challenges, marking a pivotal moment in the history of computing hardware.

Design architecture

The architecture of the Intel 1103 utilized a 1024-bit array organized as 1024 words by 1 bit, a standard for early DRAM chips. Its core employed a three-transistor DRAM cell, which differed from later one-transistor-one-capacitor cells, requiring more silicon area but offering simpler operation and better noise immunity with the PMOS logic technology of the time. The chip featured a 22-pin dual in-line package and required three supply voltages: +5V, -5V, and +12V. Critical to its operation was the need for periodic memory refresh, a characteristic of all DRAM, managed by external control logic. The interface used a multiplexed addressing scheme to reduce pin count, where row and column addresses were presented sequentially under the control of signals like RAS (Row Address Strobe).

Technical specifications

The Intel 1103 was fabricated using p-type metal-oxide-semiconductor (PMOS) silicon-gate technology, a process pioneered by Intel that allowed for higher density and performance. It had a capacity of 1024 bits, organized as 1024 x 1. The chip featured an access time of approximately 300 nanoseconds and a full cycle time of 580 nanoseconds. It operated within a temperature range of 0°C to 70°C, typical for commercial-grade integrated circuits. The device required a complex refresh cycle every 2 milliseconds to maintain data integrity, a task handled by external support chips such as the Intel 3222 refresh controller. Its power dissipation was relatively high by modern standards, at around 525 milliwatts during active operation.

Production and variants

Initial production of the Intel 1103 in 1970 faced significant challenges with low yields and reliability, but rapid improvements in semiconductor manufacturing at Intel's facilities soon made it a high-volume product. It was produced for over a decade, with later versions seeing incremental improvements in speed and power characteristics. The success of the 1103 led directly to a family of compatible and enhanced DRAMs from Intel, most notably the Intel 2104 4K DRAM. Second-source production agreements with other semiconductor firms, including Advanced Micro Devices and Texas Instruments, helped standardize the part and ensure supply for the computer industry. Variants included military-grade versions with extended temperature ranges for use in systems by contractors like Lockheed Corporation.

Impact and legacy

The Intel 1103 had a transformative impact on the computer industry, making magnetic-core memory obsolete for main memory applications within a few years due to its superior cost-per-bit and smaller physical size. This shift was instrumental in the success of new generations of minicomputers from companies like Digital Equipment Corporation and Data General, and later, the microprocessor-based personal computer. Its commercial viability proved the market for semiconductor memory, fueling massive investment in DRAM technology and triggering intense competition, often called the Memory Wars, among companies in the United States, Japan, and later South Korea. The 1103 is considered a landmark product in the history of Intel, providing crucial revenue that funded the development of the Intel 4004, the world's first commercial microprocessor. Category:Intel microprocessors Category:Computer memory Category:1970 in computing