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During the 20th Century, Vacuum Tubes Improved in a Moore’s Law-Like Way

Their improvement had to do with power density rather than miniaturization

3 min read
Progression of power density for major device types
Source: V.L. Granatstein, R.K. Parker, and C.M. Armstrong, Proceedings of the IEEE, Vol. 87, No. 5, May 1999

In the 48 years since the introduction of the first microprocessor, in 1971, the number of electronic components that can be crammed onto a given area on a chip has increased seven orders of magnitude. That corresponds to a doubling about every two years [see “Moore’s Curse,” IEEE Spectrum, April 2015].

You might think that the performance of previous vacuum-tube electronics could not possibly compare with that record of improvement. Not so. It’s just that the key metric of improvement is different.

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A Circuit to Boost Battery Life

Digital low-dropout voltage regulators will save time, money, and power

11 min read
Image of a battery held sideways by pliers on each side.
Edmon de Haro

YOU'VE PROBABLY PLAYED hundreds, maybe thousands, of videos on your smartphone. But have you ever thought about what happens when you press “play”?

The instant you touch that little triangle, many things happen at once. In microseconds, idle compute cores on your phone's processor spring to life. As they do so, their voltages and clock frequencies shoot up to ensure that the video decompresses and displays without delay. Meanwhile, other cores, running tasks in the background, throttle down. Charge surges into the active cores' millions of transistors and slows to a trickle in the newly idled ones.

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