A Handy Guide to Understand Wholesale Integrated Circuits.pdf
Integrated circuit
1.
2.
3. Integrated Circuits are usually called
ICs and popularly known as a silicon
chip, computer chip or microchip.
4. • Integrated Circuit, tiny electronic circuit used to
perform a specific electronic function, such as
amplification.
• It is usually combined with other components to
form a more complex system.
5. Electronic Components?
Miniaturized Active Devices:
1. Transistors
2. Diodes
Miniaturized Passive Devices:
1. Capacitors
2. Resistors
-> It is formed as a single unit by diffusing impurities into single-crystal
silicon, which then serves as a semiconductor material.
6. • Several hundred identical integrated
circuits (ICs) are made at a time on a thin
wafer several centimeters wide, and the
wafer is subsequently sliced into individual
ICs called chips.
7.
8. It seems that the integrated circuit was
destined to be invented. Two separate
inventors, unaware of each other's
activities, invented almost identical
integrated circuits or ICs at nearly the same
time.
9. 1958: Invention of the Integrated Circuit
As with many inventions, two people had the idea for an
integrated circuit at almost the same time. Transistors had
become commonplace in everything from radios to phones
to computers, and now manufacturers wanted something
even better. Sure, transistors were smaller than vacuum
tubes, but for some of the newest electronics, they weren't
small enough.
10. 1958: Invention of the Integrated Circuit
But there was a limit on how small you could make each
transistor, since after it was made it had to be connected to
wires and other electronics. The transistors were already at
the limit of what steady hands and tiny tweezers could
handle. So, scientists wanted to make a whole circuit -- the
transistors, the wires, everything else they needed -- in a
single blow. If they could create a miniature circuit in just
one step, all the parts could be made much smaller.
11. 1958: Invention of the Integrated Circuit
One day in late July, Jack Kilby was sitting alone at Texas
Instruments. He had been hired only a couple of months earlier
and so he wasn't able to take vacation time when practically
everyone else did. The halls were deserted, and he had lots of
time to think. It suddenly occurred to him that all parts of a
circuit, not just the transistor, could be made out of silicon. At the
time, nobody was making capacitors or resistors out of
semiconductors. If it could be done then the entire circuit could
be built out of a single crystal -- making it smaller and much
easier to produce. Kilby's boss liked the idea, and told him to get
to work. By September 12, Kilby had built a working model, and
on February 6, Texas Instruments filed a patent. Their first "Solid
Circuit" the size of a pencil point, was shown off for the first time
in March.
12.
13. But over in California, another
man had similar ideas…
14. 1958: Invention of the Integrated Circuit
In January of 1959, Robert Noyce was working at the small Fairchild
Semiconductor startup company. He also realized a whole circuit could
be made on a single chip. While Kilby had hammered out the details of
making individual components, Noyce thought of a much better way to
connect the parts. That spring, Fairchild began a push to build what they
called "unitary circuits" and they also applied for a patent on the idea.
Knowing that TI had already filed a patent on something similar,
Fairchild wrote out a highly detailed application, hoping that it wouldn't
infringe on TI 's similar device.
15. All that detail paid off. On April 25, 1961, the
patent office awarded the first patent for an
integrated circuit to Robert Noyce while Kilby's
application was still being analyzed. Today, both
men are acknowledged as having
independently conceived of the idea.
16.
17. In the early days of integrated circuits, only a
few transistors could be placed on a chip, as
the scale used was large because of the
contemporary technology, and
manufacturing yields were low by today's
standards. As the degree of integration was
small, the design was done easily. Over time,
millions, and today billions, of transistors could
be placed on one chip, and to make a good
design became a task to be planned
thoroughly. This gave rise to new design
methods.
18. Integrated circuits are often classified by the number of transistors
and other electronic components they contain:
• SSI (small-scale integration): Up to 100 electronic components per
chip
• MSI (medium-scale integration): From 100 to 3,000 electronic
components per chip
• LSI (large-scale integration): From 3,000 to 100,000 electronic
components per chip
• VLSI (very large-scale integration): From 100,000 to 1,000,000
electronic components per chip
• ULSI (ultra large-scale integration): More than 1 million electronic
components per chip
19.
20. Integrated circuits can be classified
into analog, digital and mixed
signal (both analog and digital on
the same chip).
21. Digital integrated circuits can contain anything from one to millions
of logic gates, flip-flops, multiplexers, and other circuits in a few
square millimeters. The small size of these circuits allows high speed,
low power dissipation, and reduced manufacturing cost compared
with board-level integration. These digital ICs,
typically microprocessors, DSPs, and micro controllers, work using
binary mathematics to process "one" and "zero" signals.
22. Analog ICs, such as sensors, power management circuits,
and operational amplifiers, work by processing continuous signals.
They perform functions like amplification, active
filtering, demodulation, and mixing. Analog ICs ease the burden on
circuit designers by having expertly designed analog circuits available
instead of designing a difficult analog circuit from scratch.
23. ICs can also combine analog and digital circuits on a single chip to
create functions such as A/D converters and D/A converters. Such
circuits offer smaller size and lower cost, but must carefully account
for signal interference.
24.
25. The integrated circuits offer a number of advantages over those made
by interconnecting discrete components. These are summarized as
follows:
1. Extremely small size—thousands times smaller than discrete circuit. It is
because of fabrication of various circuit elements in a single chip of semi-
conductor material.
2. Very small weight owing to miniaturized circuit.
3. Very low cost because of simultaneous production of hundreds of similar
circuits on a small semiconductor wafer. Owing to mass production
an IC costs as much as an individual transistor.
4. More reliable because of elimination of soldered joints and need for fewer
inter-connections.
5. Low power consumption because of their smaller size.
6. Easy replacement as it is more economical to replace them than to repair
them.
26. The integrated circuits offer a number of advantages over those made
by interconnecting discrete components. These are summarized as
follows:
7. Increased operating speeds because of absence of parasitic capacitance
effect.
8. Close matching of components and temperature coefficients because of bulk
produc¬tion in batches.
9. Improved functional performance as more complex circuits can be
fabricated for achieving better characteristics.
10. Greater ability of operating at extreme temperatures.
11. Suitable for small signal operation because of no chance of stray electrical
pickup as various components of an IC are located very close to each other
on a silicon wafer.
12. No component project above the chip surface in an IC as all the components
are formed within the chip.
27.
28. The integrated circuits have few limitations also, as listed
below :
1. In an IC the various components are part of a small semi-conductor chip and
the individual component or components cannot be removed or replaced,
therefore, if any component in an IC fails, the whole IC has to be replaced by
the new one.
2. Limited power rating as it is not possible to manufacture high power (say
greater than 10 Watt) ICs.
3. Need of connecting inductors and transformers exterior to the semi-
conductor chip as it is not possible to fabricate inductors and transformers
on the semi-conductor chip surface.
4. Operations at low voltage as ICs function at fairly low voltage.
5. Quite delicate in handling as these cannot withstand rough handling or
excessive heat.
29. The integrated circuits have few limitations also, as listed
below :
6. Need of connecting capacitor exterior to the semi-conductor chip as it is neither
convenient nor economical to fabricate capacitances exceeding 30 pff Therefore, for
higher values of capacitance, discrete components exterior to IC chip are connected.
7. High grade P-N-P assembly is not possible.
8. Low temperature coefficient is difficult to be achieved.
9. Difficult to fabricate an IC with low noise.
10. Large value of saturation resistance of transistors.
11. Voltage dependence of resistors and capacitors.
12. The diffusion processes and other related procedures used in the fabrication
process are not good enough to permit a precise control of the parameter values for
the circuit elements. However, control of the ratios is at a sufficiently acceptable
level.