Shopping List: Experiments 16 Through 24
152 Chapter 4
Figure 4-10. When shopping for a numeric
keypad, it should have 12 keys in “touch-
tone phone” layout, and should have at
least 13 contacts for input/output. The
contacts are visible here along the front
edge.Figure 4-11. This keypad has insufficient
pins and will not work in the circuit in this
book.BAckground
How chips came to be
The concept of integrating solid-state components into one
little package originated with British radar scientist Geoffrey
W. A. Dummer, who talked about it for years before he at-
tempted, unsuccessfully, to build one in 1956. The first true
integrated circuit wasn’t fabricated until 1958 by Jack Kilby,
working at Texas Instruments. Kilby’s version used germa-
nium, as this element was already in use as a semiconduc-
tor. (You’ll encounter a germanium diode when I deal with
crystal radios in the next chapter of this book.) But Robert
Noyce, pictured in Figure 4-12, had a better idea.
Born in 1927 in Iowa, in the 1950s Noyce moved to Cali-
fornia, where he found a job working for William Shockley.
This was shortly after Shockley had set up a business based
around the transistor, which he had coinvented at Bell Labs.
Noyce was one of eight employees who became frustrated
with Shockley’s management and left to establish Fairchild
Semiconductor. While he was the general manager of
Fairchild, Noyce invented a silicon-based integrated circuit
that avoided the manufacturing problems associated with
germanium. He is generally credited as the man who made
integrated circuits possible.
Early applications were for military use, as Minuteman
missiles required small, light components in their guidance
systems. These applications consumed almost all chips pro-
duced from 1960 through 1963, during which time the unit
price fell from around $1,000 to $25 each, in 1963 dollars.In the late 1960s, medium-scale integration chips emerged,
each containing hundreds of transistors. Large-scale inte-
gration enabled tens of thousands of transistors on one chip
by the mid-1970s, and today’s chips can contain as many as
several billion transistors.
Robert Noyce eventually cofounded Intel with Gordon
Moore, but died unexpectedly of a heart attack in 1990. You
can learn more about the fascinating early history of chip de-
sign and fabrication at http://www.siliconvalleyhistorical.org.Figure 4-12. This picture of Robert Noyce, late in his career, is
from the Wikimedia Commons.