In This Article
What is Integrated Circuit?
An Integrated Circuit or IC in short refers to the collection of a large number of electronic components such as transistors, capacitors and resistors. IC is built from a thin substrate of silicon or semiconductor material and is also known as a chip or a microchip.
- An Integrated Circuit is a chip that contains a set of electronic circuits closely entrenched in it.
- Depending on the design and build, an Integrated Circuit can perform different functions to contribute to the performance of the computer system.
- A semiconductor usually made from silicon crystal material, the Integrated Circuits are small, fast and less expensive, having a lot of varied applications in this age.
Understanding Integrated Circuit
An Integrated Circuit is a semiconductor that contains a large number of small MOSFETs, a short for Metal Oxide Semiconductor Field Effect Transistors, all integrated into a small, flat monolithic chip made from silicon.
These transistors are smaller in size but are much faster, reliable and capable.
These Integrated Circuits are the main building blocks that have eliminated the need for using discrete transistors.
An Integrated Circuit actually refers to the semiconductor wafer which you will find in all modern electronic devices, including a computer.
Just as the name suggests, it is an integrated system.
An Integrated Circuit comes with thousands, or even millions, of miniature components that are interconnected with one another.
All these components are implanted onto a thin silicon crystal semiconductor.
The components fabricated on an Integrated Circuit are:
- Capacitors and
These components perform their own functions to make the Integrated Circuits one of the most integral parts of a computer.
The Integrated Circuits have virtually reformed the world of electronics, being used in almost every electronic device whether it is the mobile phones, computers, or any other home appliances.
These inextricable parts are known by different names in the computer world such as:
- A chip
- A microchip
- A microelectronic circuit or
- Simply as an IC (This is more common however).
The semiconductor wafer can perform different functions as well, such as:
- As an oscillator
- As an amplifier
- As a timer
- As a logic gate
- As a counter
- As a computer memory
- As a micro processor and
- As a microcontroller, to name a few.
As said earlier, these semiconductor wafers contain millions of transistors, resistors, diodes and capacitors, but, depending on the design, an IC may also come with a few additional components.
Usually all these components on these semiconductor wafers made of silicon, copper or other materials are microscopic.
This results in a monolithic chip that is also very tiny, often occupying just a few square millimeters or centimeters of room.
The computer processor is one of the most common examples of an IC that may come to the mind.
These ICs often come with millions or even billions of components in them! However, all ICs are not processors.
Since the first Integrated Circuits, the design, features and functionalities have changed dramatically over the years.
Based on these changes after their initial creation, the Integrated Circuits can be divided into different generations.
Each of the succeeding generations is better than the preceding one in features, performance level, and functionalities with higher number of logic gates and transistors.
Here is the list of each of the generations of the Integrated Circuits along with the rough capacity against each.
- SSI, a short for Small Scale Integration, typically comes with 1 to 10 transistors and 1 to 12 logic gates
- MSI, a short for Medium Scale Integration, typically comes with 10 to 500 transistors and 13 to 99 logic gates
- LSI, a short for Large Scale Integration, typically comes with 500 to 20000 transistors and 100 to 9999 logic gates
- VLSI, a short for Very Large Scale Integration, typically comes with 20000 to 1000000 transistors and 10000 to 99999 logic gates and
- ULSI, a short for Ultra Large Scale Integration, typically comes with more than 1000000 transistors and 100000 logic gates.
Modern IC Design and Construction
The modern Integrated Circuits have evolved pretty fast and they are built to be faster, more powerful and much smaller in size.
These ICs are much more complex as compared to those available in the early days and are able to hold even billions of transistors and other components on them.
Typically, the modern Integrated Circuits are an all-in-one piece and each of the parts on it is typically and directly embedded into the silicon chip instead of being simply mounted on it.
There are several levels of abstraction that the modern Integrated Circuits rely on.
The fragile semiconductor wafer contains a number of intricate connections between the several layers of it.
When a number of such Integrated Circuits are combined together, it is called a die.
However, with millions or billions of parts included in one single chip, it is impossible to place and connect every component separately.
These dies cannot be soldered together to connect each other because these are too small for that.
Instead, the designers found a different way to accomplish that. They use a special kind of programming language in order to create tiny circuit elements.
They then combine them to increase the density as well as the size of the elements on the chip progressively.
This helps in meeting the application requirements more comprehensively with the use of these ‘packaged’ Integrated Circuits.
Therefore, the tiny and delicate die is turned into a black chip that you can see in almost all the electronic devices.
As of now, the most common type of Integrated Circuits used is the monolithic chips.
The two most significant parts of constructing an Integrated Circuit are fabrication and packaging.
The fabrication process involves making or designing the Integrated Circuits which includes a set of photographic as well as chemical processors.
In simple terms this is the process of designing the different circuits to fit into the semiconductor material which is also called the wafer.
The different steps that are followed during the fabrication process include:
- Lithography – In this step the exterior of the wafer is coated with a photo-resisting liquid layer and after that it is backed and hardened.
- Etching – In this step all those materials that are not necessary are separated from the wafer and the photo-resist model is shifted toward the wafer.
- Deposition – In this step several materials films are applied on the semiconductor by using either the Chemical Vapor method or Physical Vapor method.
- Oxidation – In this step the Si layers on the top are oxidized to SiO2 by oxidation of water molecules.
- Diffusion – This final step of fabrication involves enforcing lattice faults.
On the other hand, the packaging process of the Integrated Circuits, which is also known as encapsulation or assembly, is actually the last stage of making the chips.
In the early days, the packaging of Integrated Circuits was usually done in ceramic flat packs.
This process was followed for several years till DIP or Dual Inline Package was introduced.
However, irrespective of the types, the procedures for packaging the Integrated Circuits include:
- Attaching the die
- Bonding the Integrated Circuits
- Flip chip
- Quilt packaging
- Attaching the film and
- Encapsulation of the Integrated Circuits.
In most cases, the Integrated Circuits are packaged in ceramic insulation or opaque plastic which includes metal pins that are used for linking with the external world.
In the entire design process of the Integrated Circuits, there are quite a few steps that are required to be followed such as:
- Estimating the size
- Preparing the possibility report
- Designing the circuit
- Simulating the circuit
- Floor planning
- Reviewing the design
- Layout designing
- Analyzing the timing
- Generating the Automatic Test Model or ATM
- Manufacturing design
- Preparing the mask data
- Fabricating the silicon wafer
- Die testing
- Characterizing of device
- Generating data sheet and
- Producing the Integrated Circuits.
After all these steps are completed, reliability and failure testing and analysis are also needed to be made.
Types of Integrated Circuits
The Integrated Circuits may come in different forms depending on the type of application intended.
For example, it can be:
- Analog or linear
- Digital and
- Combination of the two.
Analog Integrated Circuits:
The analog Integrated Circuits will typically provide a variable output continuously depending on the level of the input signals. In theory, the analog Integrated Circuits can achieve a countless number of states.
In these types of ICs, the output signal level is usually a linear function of the input signal level.
This means that when the immediate output is graphed against the immediate input, the graph will appear to be a straight line.
The analog Integrated Circuits are quite simple in design since they usually come with only a few components.
The linear Integrated Circuits have different applications and two of the most common ones are:
- As AF or Audio Frequency amplifiers and
- As RF or Radio Frequency amplifiers.
A familiar device in which you will find these applications is the op amp or the operational amplifier.
Another widespread application of the analog Integrated Circuits is the temperature sensor.
Usually, an analog Integrated Circuit can be configured to turn different devices on or off when a particular signal reaches a specific value or temperature level. These devices include:
- Air conditioners and
Digital Integrated Circuits:
The digital Integrated Circuits, just as the name suggests, is pretty unlike the analog Integrated Circuits.
Usually, the digital Integrated Circuits do not function over an uninterrupted series of signal amplitudes.
Instead, these ICs typically work at only a few specific and discrete states or levels.
The most important building block of the digital Integrated Circuits is the logic gates.
These usually operate with binary data. A binary data is a signal that usually has only two dissimilar states that are called:
- Low or logic 0 and
- High or logic 1.
You will find a widespread use of digital Integrated Circuits today which includes and is not limited to:
- Enterprise networks
- Frequency counters.
Mixed Integrated Circuits:
A hybrid or mixed Integrated Circuit, needless to say, uses the principles of both an analog Integrated Circuit and a digital Integrated Circuit.
These specific types of Integrated Circuits may have a varied range of functions such as:
- A digital to analog converter
- An analog to digital converter or
- A clock or timer Integrated Circuit.
One of the most complex types of Integrated Circuits is the microprocessor that can handle billions of operations each second.
In a computer, a microprocessor typically contains two specific components as follows:
- The CPU or the Central Processing Unit that is the brain of the computer and performs all major functions and
- The GPU or the Graphics Processing Unit that specializes in graphics rendering to produce images and video.
In one single microprocessor there may be billions of transistors interconnected.
Each of these transistors performs a particular logic function depending on the type of instructions that it receives from the clock.
Ideally, a logic function or calculation that a transistor of a microprocessor is programmed to perform is carried out when the state of the clock changes.
It is the frequency of the clock that decides the speed at which these operations will be performed.
This specific type of Integrated Circuit also comes with several different types of registers and prearranged memory locations to store information. These are:
- A permanent register which stores predetermined instructions for different operations.
- A temporary register which stores numbers that must be operated on as well as the result of that particular operation
- A counter which holds the memory address of the following instruction
- A stack pointer which holds the address of the preceding instruction that is put into the stack memory and
- A memory address register which holds the address of the data that is to be worked on.
The modern manufacturers and distributors further divide the Integrated Circuits into other categories as follows.
The digital Integrated Circuits are further sub-categorized as:
- Logic Integrated Circuits such as the microprocessors and microcontrollers
- Memory chips such as floating gate memory and MOS or Metal Oxide Silicon memory
- Interface Integrated Circuits such as level shifters, serializer and deserializer
- Power management Integrated Circuits and
- Programmable devices on the whole.
The hybrid on mixed signal Integrated Circuits are also grouped into different other additional heads such as:
- Data acquisition Integrated Circuits which includes digital potentiometers
- Switched Capacitor or Integrated Circuits and
- RF CMOS Integrated Circuits.
Then there are also those three-dimensional Integrated Circuits that are divided into different heads such as:
- Through Silicon Via or TSV Integrated Circuits and
- Cu-Cu connection Integrated Circuits.
And of course, there are the Application Specific Integrated Circuits. It can either have an analog or a digital circuit.
Since these ICs are application specific, it is not possible to reconfigure them.
This means that these Integrated Circuits can perform only one particular function.
For example, a remote control car that comes with a speed controller Integrated Circuit is typically hard-wired to do that particular job only.
It can never become or be used as a microprocessor.
This is mainly because the Application Specific Integrated Circuits do not have the capability to follow alternate commands.
With such a variety, the Integrated Circuits show that it has come a long way from the days of ENIAC to be what it is today – the key component of almost all modern electronic devices.
Uses of Integrated Circuits
You will find an Integrated Circuit in almost all major types of electronic devices such as:
- Computers and its different peripherals such as keyboards, mice and others
- Audio system such as speakers, headphones, and microphones
- Mobile phones and smartphones
- Wearables such as smartwatches
- Smart speakers such as Google Home and Amazon Echo
- Digital video or photo cameras
- Video game consoles and related controllers
- Infotainment systems that are typically used in vehicles
- Smart home LED lights
- Smart electrical wall outlets
- Network switches
- Home appliances such as washing machines, microwaves, toasters and others
- Televisions and lots more.
The most common types of Integrated Circuits used in these devices are:
- Logic Gate Integrated Circuits which is a combined circuit that produces logical outputs depending on the diversity of input signals which may be two or three but the output will only be one always
- Timer Integrated Circuits which comes with precise timing cycles with a 50 % or 100 % duty cycle
- Operational amplifier Integrated Circuits which is actually a high gain voltage amplifier that produces a particular end output with a disparate input and
- Voltage regulator Integrated Circuits that generate a steady DC output notwithstanding the variances in the DC input.
The Integrated Circuits are extremely versatile and that is why they have such a widespread application and uses.
Working Process of Integrated Circuits
The working process of the Integrated Circuit is very much the same as that of the timer, amplifier, oscillator, microprocessor, and the computer memory as well.
The numerous components like the resistors, transistors, capacitors, and others on the small silicon chip carry out different calculations and functions. The data used and derived is typically stored by using either digital or analog technology.
In the case of the digital Integrated Circuits, the logic gates are used in order to carry out an instruction.
These gates, as said earlier, simply work on two specific values – ones and zeros.
When a low signal is sent out over the digital Integrated Circuit to a component, it will give a zero value.
On the other hand, when a high signal is sent through the digital IC it will produce a 1 value.
These Integrated Circuits are usually used in computers, networking equipment and consumer electronic devices.
On the other hand, the analog Integrated Circuits perform linear functions using permanent values.
This means that these types of circuits can use any type of value and generate an output of a different value. Therefore, the linear Integrated Circuits use the o/p value for working.
Now, the different components of the Integrated Circuits also perform different functions independently to contribute to the working process which involves multiple tasks and calculations as explained below.
The diodes in the Integrated Circuits are the particular electronic devices that control the flow of current through the circuit.
These components also control the direction of the flow of current, which is particularly in a specific path.
The transistors in the Integrated Circuits typically store the circuit stabilizer that controls the voltages.
These are used to increase the strength of the given signal. In the digital Integrated Circuits these typically act as the switches that allow a definite amount of voltage to pass through the circuit when the gate opens which allows that particular amount of voltage to pass through.
The microprocessors of the Integrated Circuits are considered to be the most crucial component that provides the desired memory to the computer system.
Similarly, the microprocessors also provide memory for performing calculations.
All these are done in accordance to a specific logic or protocol. Based on this logic or protocol the microprocessors process the electricity and data inside the system.
This means that, in such situations, the microprocessors behave like the operating system of the Integrated Circuit.
This allows the different components in it to interact with each other.
Characteristics of Integrated Circuits
It is the features of the Integrated Circuits that make them so useful in all fields.
Right from its design and construction to its packaging, everything needs a special mention, as follows.
Size and Nature of Material:
The small size and delicate nature of these silicon chips does not overheat.
This is because small gold and aluminum wires are tied together and molded into a flat, plastic or ceramic block along with the metal pins on the exterior of the block that link to the cables inside.
The size of the Integrated Circuits typically ranges between 1 square mm to an excess of 200 mm making it extremely small to fit inside anything.
As said earlier, the Integrated Circuits are made up of semiconducting materials.
This means that it is well in between a good conductor such as copper and an insulator such as plastic.
The silicon material of the semiconductor is however the current favorite because it is considered to be an ultrapure material that comes with hints of other elements as well in it in small but precise amounts.
These additional elements help in inducing different characteristics into the electronic materials.
Then, when you look at the packages of the Integrated Circuits, you will see the diverse types.
For example, the simple chips come in DIP or a Dual Inline Package in the shape of a long rectangle consisting of 4, 7, 8 or more pins on each side.
Over the years, however, the number of pins has grown to keep up with the ever growing complexity of the Integrated Circuit designs.
The designers have even included hundreds of pins onto a few particular types of microprocessors.
All these pins are arranged neatly in different rows located at the bottom of the Integrated Circuit.
The number of transistors or density of the Integrated Circuit has also grown considerably to ensure a higher, better, and a faster performance.
For example, just a decade ago, or in the year 2009 to be more precise, the transistors on a few specific types of chips measured 45 nanometers, which is equivalent to billionths of a meter, on each side.
This extremely small size allowed incorporating more than 100 million transistors on the chips.
This is in keeping with Moore’s Law which states that the number of transistors on a chip will double in every two years.
The semiconductor industry has been following this law since the 1960s.
It is needless to say that, as the density of the chip grows, so does the functionality.
The fact that these circuits are integrated combines several devices on one chip that performs different sub-functions.
This means that these functions that were performed by several chips before are now performed by only one which adds to the performance level and speed.
For example, a microcontroller has a microprocessor, an interface, and a memory all in one to make and perform as a complete unit.
A few other notable characteristics of the Integrated Circuits are:
- A complicated layering of semiconductors
- A fragile wafer
- A die
- A set of highly intricate connections
- A compact size
- An easily connectable and unique package
- Polarized location and
- Unique function.
Also, the pins increase in a sequence around the chip once it is identified. This usually happens in an anti clockwise manner.
Advantages of Using Integrated Circuits
If you compare the Integrated Circuits with the discrete circuits, there are two distinct advantages in the form of cost and performance.
The cost of the Integrated Circuits is typically lower than the discrete chips because these chips that contain several components are printed by using photolithography as a single unit and not built by each transistor at a time.
As for the performance, it is high for the Integrated Circuits because the components on these chips can switch quickly.
In the process they consume relatively less power than the discrete circuits, once again due to their proximity and small size.
Some of the other advantages of using an integrated Circuit are:
- Very small size
- Lesser weight
- High reliability due to relatively low rate of failure due to temperature rise and
- Easy replacement.
In addition to that, the packaged Integrated Circuits also need less material to build due to their smaller size in comparison to the discrete circuits which also reduces the cost significantly.
However, there are a few specific disadvantages of using an Integrated Circuit, which are also quite good to know at this point.
One of the most significant downsides of the ICs is that if a particular component in it fails, it will make the whole circuit unusable and you will have to replace it completely with a new one.
This is because the indicators, coils and other elements in an Integrated Circuit cannot be fabricated easily or directly.
Another major demerit of the Integrated Circuits is that it can handle only a small amount of power which means that high voltage and low noise may not be easily obtained.
Usually, the power dissipation of an IC is restricted to 10 watts only.
Moreover, the resistor and capacitors of the ICs are normally voltage dependent which does not make them as flexible as they should be, and its transformers are impossible to fabricate.
From Which Generation Integrated Circuits Were Used in Computers?
The Integrated Circuits were used for the first time in the 3rd Generation computers, which is within the year 1964 and 1971.
This replaced the discrete transistors used in the 2nd Generation computers, which itself replaced the vacuum tubes used in the 1st Generation computers.
This transformation resulted in a considerable increase in the efficiency and speed of the computers.
Is a CPU an Integrated Circuit?
Well, looking at the hardware level, a Central Processing Unit or CPU is surely an Integrated Circuit and is referred to as a chip.
However, technically speaking, a CPU is a function and can be defined by what it actually does whereas Integrated Circuit refers to a specific technology.
Still, it can be said that all CPUs are ICs but all ICs are not CPUs.
So, with all that said and explained about the Integrated Circuits, this article comes to an end.
You surely are well versed about the Integrated Circuits used today in the computers, as well as in many other devices, so much that you can even share your knowledge to a few of your ignorant friends and colleagues.