Integrated Circuit (IC)
Normally diodes, bipolar junction transistors (BJT) and field effect transistors (FET) are commonly used electronics component in circuit. These components are interconnected along with required capacitors and resistors to form a circuit. These circuit is known as discrete circuit. In it each of the components can be separated from the circuit as when required. Nowadays there is a new trend of making an electronic circuit where on a semiconductor wafer large numbers of capacitors, diodes and transistors are permanently fabricated.
As the components in this type of circuit are not separate that is integrated on the semiconductor wafer, this circuit is commonly known as Integrated Circuit.
The transistors that we have been able to fit into IC, has rapidly increased since their formation, doubling approximately every 2 years. This is known as Moore’s Law, and is often cited as an explanation for the exponential growth of technology over the last 50 years. There are two type of IC.
Types of Integrated Circuits (ICs)
There are two main types of IC:
- Digital ICs
- Analog ICs
These types of ICs are explained in detail below.
In this, the input and output signal both are continuous. The output signal waveform depends upon the input signal waveform and the output signal is a linear function of input signal. Linear ICs are most commonly used as radio frequency amplifier and audio frequency amplifier. Operational amplifiers, voltage regulators and timers are also well-known examples of linear ICs or analog ICs.
The logic Gates, such as AND, OR, NAND, XOR gate, flip flops, counters; microprocessors are some common examples of digital ICs. These ICs operate on binary data such as 0 or 1. Normally in digital circuit, 0 indicates 0 Volts and one indicate +5 Volts. Digital ICs are commonly used in many electronics circuits.
The main components in an IC chip are transistors. These transistors may be BJT or FET upon the applications of ICs.
As the technology is going advance, the number of transistors in a single IC chip is also increasing. Depending upon the number of transistors in a single chip, the ICs are categorized in five groups. Namely,
|i)||Small Scale Integration (SSI); where the number of transistors in a single IC chip is up to 100.|
|ii)||Medium Scale Integration (MSI); where the number of transistors in a single IC chip is range from 100 to 1000.|
|iii)||Large Scale Integration (LSI); where the number of transistors in a single IC chip is range from 1000 to 20,000.|
|iv)||Very Large Scale Integration (VLSI); where the number of transistors in a single IC chip is range from 20,000 to 10,00,000.|
|v)||Ultra Large Scale Integration (ULSI) where the number of transistors in a single IC chip is range from 10,00,000 to 1,00,00,000.|
ICs can be further classified as bipolar ICs and uni polar ICs depending upon the active devices that used in ICs. In bipolar ICs the main components are BJT , whereas in unipolar ICs the main components are FET or MOSFETs.
IC Manufacturing Process
There are two types of IC manufacturing technologies one is hybrid technology and other is monolithic technology. In monolithic technique, all components and their interconnections are manufactured together into a single silicon chip. This technology is applied when identical ICs chip to be produced in large scale. Monolithic ICs are cheap but reliable.
In hybrid ICs, separate components are connected on a ceramic substance and interconnected by wire.
Advantages of Integrate Circuit
The advantages of integrated circuits (ICs) include:
- It is very small in size practically around 21,000 electronic components can be incorporated in a single square of IC chip.
- Many complex electronic circuits are fabricated in a single chip and hence this simplifies the designing of a complex circuit. It also improves the performance of system.
- High reliability of ICs.
- Due to bulk production these are available at low cost.
- It consumes very tiny power.
- It has high operating speed due to absence of parasitic capacitance effect.
- It is easily replaceable from the mother circuit.
Disadvantages of Integrate Circuit
The disadvantages of integrated circuits (ICs) include:
- Due to its small size, IC is unable to dissipate heat when current in it increased. That is why ICs are often damaged due to over flow of current.
- Transformers and Inductors cannot be incorporated in ICs.