Digital Circuit Design Scaling tends to emphasize other deficiencies of the abstraction-based approach. Global entities, such as clock signals and supply lines, are significantly affected by scaling. Clock distribution, circuit synchronization and supply-voltage distribution are becoming more and more critical. New design issues emerge over time. Power dissipation issue periodically re-emerges.
Trouble shooting an erroneous design requires circuit expertise.
The VLSI Testing Process A process applied to hardware devices whose goal is to determine if the device is free of fabrication defects that would otherwise cause the device to violate its functional or parametric specifications. It is applied to every device and therefore needs to be simple and fast. For logic test, we are done as soon as we observe the first error. However, we may be interested in locating the fault as well, for chip or process debug. The objective of diagnosis is to determine the location of the fault.