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The Surprising Story of the First Microprocessors

You thought it started with the Intel 4004, but the tale is more complicated

12 min read
Photo: INTEL
Photo: INTEL

Transistors, the electronic amplifiers and switches found at the heart of everything from pocket radios to warehouse-size supercomputers, were invented in 1947. Early devices were of a type called bipolar transistors, which are still in use. By the 1960s, engineers had figured out how to combine multiple bipolar transistors into single integrated circuits. But because of the complex structure of these transistors, an integrated circuit could contain only a small number of them. So although a minicomputer built from bipolar integrated circuits was much smaller than earlier computers, it still required multiple boards with hundreds of chips.

In 1960, a new type of transistor was demonstrated: the metal-oxide-semiconductor (MOS) transistor. At first this technology wasn’t all that promising. These transistors were slower, less reliable, and more expensive than their bipolar counterparts. But by 1964, integrated circuits based on MOS transistors boasted higher densities and lower manufacturing costs than those of the bipolar competition. Integrated circuits continued to increase in complexity, as described by Moore’s Law, but now MOS technology took the lead.

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Video Friday: Humanoid Soccer

Your weekly selection of awesome robot videos

4 min read
Humans and human-size humanoid robots stand together on an indoor soccer field at the beginning of a game

Video Friday is your weekly selection of awesome robotics videos, collected by your friends at IEEE Spectrum robotics. We also post a weekly calendar of upcoming robotics events for the next few months. Please send us your events for inclusion.

CoRL 2022: 14–18 December 2022, AUCKLAND, NEW ZEALAND
ICRA 2023: 29 May–2 June 2023, LONDON

Enjoy today’s videos!

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Array of devices on a chip

This analog electrochemical memory (ECRAM) array provides a prototype for artificial synapses in AI training.

IBM research

How far away could an artificial brain be? Perhaps a very long way off still, but a working analogue to the essential element of the brain’s networks, the synapse, appears closer at hand now.

That’s because a device that draws inspiration from batteries now appears surprisingly well suited to run artificial neural networks. Called electrochemical RAM (ECRAM), it is giving traditional transistor-based AI an unexpected run for its money—and is quickly moving toward the head of the pack in the race to develop the perfect artificial synapse. Researchers recently reported a string of advances at this week’s IEEE International Electron Device Meeting (IEDM 2022) and elsewhere, including ECRAM devices that use less energy, hold memory longer, and take up less space.

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