By Tets Maniwa
EEdesign
Traditionally, electronic design automation (EDA) has been associated with IC design. The
first tools were for transistor-level simulation;they evolved at Cal Berkeley to become
Spice. The next class of tools were the computer-aided design (CAD) tools that helped
designers interconnect the individual devices. Because these were the only tools available,
CAD and EDA became synonymous with the IC design process.
This grouping of all EDA as IC design continues today. There are more than 150 IC design,
verification and analysis tools in some companies, and the bulk of the EDA revenues come
from the IC design sector. Although some add the additional category of computer aided
manufacturing (CAM), that is more related to the actual manufacturing functions of running
a factory.
The problem with this narrow definition of EDA is that it excludes some significant
categories of tools. Electronic systems include many components besides ICs-there are
printed-circuit boards, packaging, wiring and even software. To take the collection of
components beyond the condition of a box full of parts, the manufacturing side must perform
many assembly and test operations as well as test and analyze reliability and quality
assurance.
As systems move through the continuum of processes of design and manufacturing, one of the
important functions is the design for manufacturability (DFM) assessment. In the IC design
phase, this review occurs after physical design in the parasitic extraction and analysis
tools. The analysis may miss some important factors because the IC design process is
fragmented into facets of consideration like timing, power, noise and reliability. The
point tools that look at the various functions work in relative isolation.
At the pc-board level, the DFM analysis considers physical and electrical parameters like
dimensions, noise and crosstalk, and device placement and placement order. This analysis
phase starts to let the manufacturing considerations like vendor quality and delivery
capabilities intrude into the review. A pc board might have a problem in manufacturing at
one vendor, or some selected components may have unusual delivery or quality constraints.
These constraints need to be addressed as early in the design cycle as possible to avoid
problems in the first system deliveries.
Another area where manufacturing concerns enter is test. Even though a large majority of IC
designers claim to consider design for test (DFT) as a part of the design function, most
systems do not get anything more than component-level testing provided as part of the
design-to-manufacturing handoff. The paucity of system-level test functions means that the
manufacturing engineers have the same type of problem that the IC designers have in
incorporating system-level function blocks into the design. The function block may have
test vectors, but the operating environment is different because the part is no longer
isolated.
The transition from design, to (virtual) prototype, to final product requires a wide
variety of engineering disciplines and development tools. When engineers integrate entire
systems onto a few pieces of silicon, the divisions among the various development teams-
hardware, software, test and manufacturing-become blurred. Formerly easy or arbitrary
decisions at the design level now have adverse consequences in other areas if the teams
don't work closely together throughout the design cycle.
An inclusive view of EDA will look at all areas of electronic design where the application
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