CMPS 375 Computer Architecture
Integrated Circuit Package
Densities
Integrated circuits may be classified as SSI (Small-Scale
Integration), MSI (Medium-Scale Integration), LSI
(Large-Scale Integration), VLSI (Very-Large-Scale
Integration), and SLSI (Super-Large-Scale Integration). The
various levels of integration are based on the numbers of
gates or transistors that are packed onto a single chip.
The classification is not an exact science; it varies from
expert to expert as shown in the following table. Reference SSI MSI LSI VLSI
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Tanenbaum 1-10 10-100 100-100,000 >100,000
Livadas 3-30 30-300 300-3,00 >3,000
MS Press <10 10-100 100-5,000 5,000-50,000
Null 10-100 100-1,000 1,000-10,000 >10,000
CMPS375 <10 10-100 100-10,000 >5,000
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References
Tanenbaum, A., Structured Cpmputer Organization, p.
128 (1999)
Livadas, P. and C. Ward, Computer Organization, p. 84
(1993)
Microsoft Press Computer Dictionary, Third Edition,
p. 255 (1997)
Null, L. and J. Lobur, Computer Organization and
Architecture, p. 22 (2003)
Generations of Computers
The First Generation (Vacuum tube technology, 1946-1959)
The Second Generation (Transistor technology, 1960-1964)
The Third Generation (Integrated circuit technology, 1965-1980)
The Fourth Generation (Very Large Scale Integration, 1980-?)
Integrated Circuit Technologies
Two broad categories of integrated circuit technology are (1)
bipolar and (2) metal-oxide-semiconductor (MOS). Two of the
principle characteristics of the different semiconductor technologies and
families are performance and power dissipation. The
performance of a gate is the time taken by the gate to respond to input
signals. This is called propagation delay. The more power
a gate requires to operate, the more heat it generates. When many
gates are packed together, the heat generation becomes an important
consideration. The following table shows some important
characteristics of the popular logic families: Characteristic TTL ECL CMOS
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Propagation delay (ns) 5 to 10 1 to 2 25
Power dissipation (mw) 2 to 10 25 0.1
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(ns=nanoseconds); mw=milliwatts)