Like all new technologies, it took a while for engineers to accept and
promote the PCB. In the 1960s, Zeneth used to brag about using
point-to-point wiring (
Figure 1). Now everything is done with a
PCB. For years the PCB was relegated to unsung hero status in electrical
engineering. Managers considered PCB layout a trivial manufacturing
problem, not a concern for a design engineer. But as digital circuits
got faster and RF circuits got put on PCBs, the circuit board became the
limiting factor in many designs. Computer-aided design (CAD) helped
engineers design the boards, but the CAD autorouters often caused even
more problems.
Figure 1 This 1948 Motorola VT-71 "Golden View" 7-inch television set used point-to-point wiring (Source: Wikimedia/Westernelectric555).
The centrality of your PCB
My mentor,
Big John Massa,
taught me the centrality of the PCB to a design effort. Massa was
always looking for new ways to design and build circuit boards. When our
peers were talking about instruction-caching architectures in 68020
chips, Massa was talking about circuit board layout programs and
overnight
prototyping.
Massa
noted, “In my 40 years doing electronics, it’s always the circuit board
that is the holdup and the limiting factor of every project.” You don’t
just make a pile of schematics for a living. You have a higher
obligation to see that those schematics turn into something that can be
built and sold.
The modern PCB is not just a
schedule killer, it’s a critical component that has precise design
requirements. The operating frequencies and rise- and fall-times of the
signals in electronics are faster and faster. So the PCB has become more
and more important.