ASIC Design Manual

With an ever more rapid development of electronic systems, it is vital that
today’s engineering groups have access to optimal design solutions. Since the
advent of integrated circuits, manufacturers of electronic systems have used
each new generation of ICs to improve products by adding features, reducing
size, improving performance and steadily reducing product costs. To be
competitive in today’s marketplace, electronic-based products must remain
state-of-the-art. As the scale of semiconductor integration increases and
electronic systems become more complex, state-of-the-art often means use of
custom LSI circuits.
In this situation, standard, “off-the-shelf” components are often impractical;
they offer the quickest, but costly solutions. Compared to standard, off-theshelf
ICs, fully-customized components would give the lowest unit cost as well
as represent minimum chip solutions tailored to specific application needs.
However, they take a long time — usually one to three years — of tedious
development cycles.
Application-specific integrated circuits (ASICs) are devices where the circuit
is dedicated to designer’s specific requirements, and the functionality of the
circuit is totally controlled by the designer. Compared to merchant IC
implementations, ASICs offer lower system cost due to significant reductions
in component count, board area, and power consumption. Product reliability
and equipment maintainability — strong functions of component count — are
greatly improved. Compared to full-custom LSI circuits, ASICs offer several
advantages: lower development cost, shorter development time, and shorter
production lead time. Low development cost means that the LSI
implementation of your logic design is cost-justified at much lower volume
than a full-custom circuit.
Toshiba prides itself on providing its customers with unique and complete
ASIC products and services. Three main techniques of our ASIC products,
gate arrays, cell-based ICs, and embedded arrays, form the background to
procedures described in this manual.