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ASIC - Application-Specific Integrated Circuit
The cost of developing an ASIC has to be compared with the cost
of using an existing part. The existing part may not perform
the required function exactly, requiring either a design specification
change, or some additional glue logic to adapt the part
to the application.
More than one ASIC may be needed under any of the following
conditions:
- application specific functions are physically distant
- application specific functions require different technologies
- application specific functions are just too big for one ASIC
- it is desired to split the cost and risk or reuse part of the system
later on.
Factors to consider on a per chip basis:
- pad count limitation (pad density limit of 15 per mm)
- power consumption limitation (powers above 5 Watts need special attention)
- gate count limitation (above 500 kgates is getting big for CMOS)
- speed of operation --- influences choice of technology
- will it be core or pad bound ?
- special considerations :
- special static or dynamic RAM needs
- analogue parts - can these also be integrated onto the ASIC ?
- high power handling outputs for load control: e.g.~motors.
- availability of a developed module for future reuse.