The Changing Style of Electronics
As the electronics industry matures, slow but substantial changes are taking place in how an engineer goes about circuit design. By the '70s and '80s, some of the early ICs were obsolete and no longer used because they were replaced by clearly superior parts. By 1980, nobody used the Intel 4004 microcomputer any more, nor was the venerable 8008 used in new designs. RTL was replaced by TTL, then low-power Schottky TTL. Today, even HC and HCT families of CMOS TTL-compatible logic are waning. The 741 op-amp was also largely eclipsed by better parts, and it too is not incorporated into new designs.
In the earlier days, integrated-circuit fabrication facilities did not cost nearly as much as now. Even a decade ago, a state-of-the-art fab facility cost $1.5 billion, a serious investment for even a large semiconductor company. The decades of the '70s and '80s were a different world.
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