http://www.ave.nikon.co.jp/pec_e/society/story0201.htm
An Integrated Circuit (IC) is an electronic circuit consisting of one silicon semiconductor substrate (chip) on which a number of these electronic components (elements) are mounted.
ICs can be classified based on the degree of integration (the number of elements mounted on a single chip) -- examples include Large-Scale Integration (LSI) and Very Large-Scale Integration (VLSI). The term “IC” is used to refer to all classifications of semiconductor integrated circuits, from SSIs to ULSIs.
ASIC is the acronym for Application-Specific Integrated Circuit. Generally, the term refers to ICs designed by an electronic device manufacturer for use in its own products. Because ASICs are designed and manufactured to provide specific functions for electronic devices such as mobile phones, PDAs and game machines, they deliver superior performance and functionality. ASICs are employed in various consumer and industrial electronic devices.
A system LSI refers to a large-scale IC into which an entire system consisting of multiple LSIs -- CPU, memory, peripheral circuits and ASICs -- are integrated. System LSIs are mounted in electronic devices such as mobile phones, digital still cameras, portable audio devices and game machines, all of which require ICs that are small and consume relatively little power.
The System on Chip (SoC) offers a higher degree of functionality than a system LSI. An SoC comprises microprocessors, chip sets, memories, and video chips. This single chip boasts all of the functions of a computer. SoCs deliver benefits such as reduced mounting space, lower power consumption and higher cost-efficiency. As such, they are used in information communication devices such as personal computers and mobile phones, and are also found in digital home appliances like digital still cameras, digital televisions and game machines, and car navigation systems.
System LSIs and SoCs, both of which offer extremely high-level functionality on a single chip, are ICs that incorporate the advanced technologies necessary to drive today’s mobile phones and the components and devices of the burgeoning digital broadcasting industry.
