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June 1969 Electronics World
Table of Contents
Wax nostalgic about and learn from the history of early electronics. See articles
from
Electronics World, published May 1959
- December 1971. All copyrights hereby acknowledged.
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Mr. Lothar Stern was
a fairly prolific publisher of books and magazine articles during his long career
at Motorola. What remains of the Motorola brand these days is mostly associated
with cellphones, with the venerable
Razr model
being the most famous. China-based
Lenovo now owns even that aspect of Motorola (after a short-lived ownership
by Google). In its heyday prior to the 2000s, Motorola was a major manufacturer
of analog, RF, and digital semiconductors (including microprocessors), radios, televisions,
telephones, vacuum tubes, medical equipment, and more. It is interesting to note
that the issues referenced in this article regarding technical terms are not even
relevant anymore.
See Lothar Stern's article titled "Silicon Controlled Rectifiers - New Applications in the Home,"
in the October 1963 issue of Electronics World.
Some "Technical Terms" Aren't
 Engineer, teacher, editor, and author, Lothar
Stern has been involved in communicating electronic technology for the past 18 years.
After receiving his B.S. in television engineering, he worked as an electronics
engineer and instructor of electronic engineering and servicing for several years.
In 1961 he joined the Semiconductor Products Division of Motorola as Manager of
the Technical Information Center, charged with the responsibility of conveying the
changing aspects of semiconductor technology to semiconductor users. He is the author
of several books.
Guest Editorial
By Lothar Stern, Manager Technical Information Center, Motorola Semiconductor
Products Inc.
It is deplorable that a field as technically precise as semiconductor electronics
should be so permeated by ambiguities in vocabulary that even those directly involved
are finding it increasingly difficult to communicate. In part, this is an unfortunate
but perfectly understandable condition in a rapidly advancing technology. For example,
we can no longer expect the word "transistor" to convey a definite meaning without
modifying it by the adjective "bipolar" or "field-effect." Nor can we speak meaningfully
of an "integrated circuit" without qualifying it in terms of structure (i.e., monolithic,
hybrid, etc.). But, in addition to the word explosion brought on by the expansion
of functions and processes, we find ourselves victimized by the proliferation of
terms without clear-cut meaning or value. Such a term is the overworked acronym
"LSI."
Anyone connected with electronics in any way probably knows that LSI stands for
"large-scale integration." It's a good bet, however, that out of any group of three
engineers chosen at random, no two will define it the same way.
There's no record of how this term got its start. But so ambiguous has the word
become that one executive in the industry has disgustedly defined LSI as "large-scale
insanity," while an engineer has been quoted as saying that, "LSI is anything more
complex than anything we can make today."
There have been attempts, of course, to define LSI more quantitatively. One group
proposed that any monolithic circuit composed of more than "100 gates" should be
called LSI. This was amended to "100 equivalent gate functions" (whatever that is),
when it was pointed out that linear circuits, too, might become very complex.
Finally, when challenged with the question of what a monolithic circuit of only
99 gates might be called - well, what is more logical than to coin another completely
ambiguous term, Medium-Scale Integration (MSI). Thus, MSI might be defined as any
circuit larger than small-scale integration, but smaller than large-scale integration.
The big problem of placing numbers on LSI is, of course, the changing technology.
While a 100-gate circuit might have seemed difficult three years ago, it certainly
is within the realm of practicality today. And within a year or two, such circuits
are likely to be very simple in comparison with the state of the art.
Another school of thought has it that, to achieve LSI-status, a circuit must
have two or more layers of interconnecting metallization. The rationale for this
line of reasoning is that no circuit with the interconnecting metal on the same
plane as the components themselves can achieve a high enough order of complexity
for LSI. The fallacy here is that multilayer metallization technology is rapidly
becoming so routine that it is being adopted, for economic reasons, even for some
of the not-so-complex devices. Obviously, this definition won't stand up either.
One might be tempted to avoid the entire LSI/MSI hassle by ignoring the terms
altogether, were it not for the fact that provocative headlines and ad copy continually
remind us that something unusual and very exciting is happening in our technology.
And how the reader interprets this liberally used term is usually quite incidental.
In the absence of any industry agreement through the EIA, we proffer the following
definition, which is currently endorsed by and practiced at Motorola Semiconductor.
LSI is the simultaneous realization of large area circuit chips with optimum
component packing density, for the express purpose of reducing circuit costs by
maximizing the number of system interconnections performed at the chip level.
Note here the complete freedom from the "tyranny of numbers." Not a hint as to
process or manufacturing technique. Simply a statement of goals that, to its credit
and its detriment, can be construed to fit any complex integrated circuit - including
those envisioned for tomorrow as well as those in existence today.
Posted September 13, 2024
(updated from original
post on 5/9/2017)
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