PCB Design Examples - Some Case Studies
A basic analysis of historical samples, as shown here, indicates practical design densities. Given some basic data about the physical attributes of a design, the viability of a proposed PCB may be predictable. Of interest will be the total number of physical / electrical pins and the usable board area on each side.
Consideration should also be given to requirements such as high-voltages, step-&-repeat circuits, the proportion of digital vs. analog signals, impedance control, connection length/delay constraints, or other unusual design aspects.