Cell Libraries, IP-based Design, Hard and Soft Macros
Cell libraries of logical primitives are usually provided by the device manufacturer as part of the service. Although they will incur no additional cost, their release will be covered by the terms of a non-disclosure agreement (NDA) and they will be regarded as intellectual property by the manufacturer. Usually their physical design will be pre-defined so they could be termed "hard macros".
What most engineers understand as "intellectual property" are IP cores, designs purchased from a third-party as sub-components of a larger ASIC. They may be provided as an HDL description (often termed a "soft macro"), or as a fully routed design that could be printed directly onto an ASIC's mask (often termed a hard macro). Many organizations now sell such pre-designed cores — CPUs, Ethernet, USB or telephone interfaces — and larger organizations may have an entire department or division to produce cores for the rest of the organization. Indeed, the wide range of functions now available is a significant factor in the phenomenal increase in electronics in the late 1990s and early 2000s; as a core takes a lot of time and investment to create, its re-use and further development cuts product cycle times dramatically and creates better products. Additionally, organizations such as OpenCores are collecting free IP cores paralleling the open source movement in software.
Soft macros are often process-independent, i.e., they can be fabricated on a wide range of manufacturing processes and different manufacturers. Hard macros are process-limited and usually further design effort must be invested to migrate (port) to a different process or manufacturer.
Read more about this topic: Application-specific Integrated Circuit
Famous quotes containing the words cell, hard and/or soft:
“Let man consider what he is in comparison with all existence; let him regard himself as lost in this remote corner of nature; and from the little cell in which he finds himself lodged, I mean the universe, let him estimate at their true value the earth, kingdoms, cities, and himself. What is a man in the infinite?”
—Blaise Pascal (1623–1662)
“Parenting can be established as a time-share job, but mothers are less good “switching off” their parent identity and turning to something else. Many women envy the father’s ability to set clear boundaries between home and work, between being an on-duty and an off-duty parent.... Women work very hard to maintain a closeness to their child. Father’s value intimacy with a child, but often do not know how to work to maintain it.”
—Terri Apter (20th century)
“When as that Rubie, which you weare,
Sunk from the tip of your soft eare,
Will last to be a precious Stone,
When all your world of Beautie ‘s gone.”
—Robert Herrick (1591–1674)