Re: tunnel diodes retrace lines in curve tracer
Tunnel diodes excited a lot of interest for about a decade after their commercial introduction. In fact, TDs and the first IC from Fairchild (a four-transistor flip-flop) competed for attention at what is now the ISSCC conference, in 1961. The press largely ignored the IC. Articles from that time were obsessed with the tunnel diode instead. The future was going to be powered by TDs. Supercomputers, satellites, Dick Tracy wristwatch TVs...all were Coming Real Soon (tm), thanks to TDs. Then reality hit: Yes, they were much faster than contemporary transistors, but they were two-terminal devices. Making a chain of amplifiers was difficult because a change in load /here/, rippled all the way back to the input /there/. The same problem afflicted networks of logic gates. So scaling up to large systems seemed unlikely. Various desperate, complicated arrangements were devised in an effort to fix that and other practical problems, but the added complexity nullified the putative advantages of the TD. After a few turns of the Moore's law crank, it was clear that the IC was the future, and the TD gradually became the answer only to trivia questions.toggle quoted messageShow quoted text
Prof. Thomas H. Lee
Allen Ctr., Rm. 205
350 Jane Stanford Way
Stanford, CA 94305-4070
On 2/18/2021 13:54, saipan59 (Pete) wrote:
My understanding is that by the 1970's or so, TD's were obsolete because most of the practical circuits that used them could be done cheaper with modern transistors and IC's.