ABSTRACT

The circuit diagram of a simple 100 watt inverter using IC CD4047 and MOSFET IRF540.

The circuit is simple low cost and can be even assembled on a veroboard.

CD 4047 is a low power CMOS astable/monostable multivibrator IC. Here it is wired as an

astable multivibrator producing two pulse  trains of 0.01s which are 180 degree out of phase

at the pins 10 and 11 of the IC. Pin 10 is connected to the gate of Q1 and pin 11 is connected

to the gate of Q2. Resistors R3 and R4 prevents the loading of the IC by the respective

MOSFETs. When pin 10 is high Q1 conducts and  current flows through the upper half of the

transformer primary which accounts for the positive half of the output AC voltage. When pin

11 is high Q2 conducts and  current flows through the lower half of the transformer primary

in opposite direction and it accounts for the negative half of the output AC voltage.

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CHAPTER-1

1.CIRCUIT DESCRIPTION

1.1.INTRODUCTION:

Inverter is a small circuit which will convert the direct current (DC) to alternating current (AC). The power of a battery is converted in to’ main voltages’ or AC power. This power can be used for electronic appliances like television, mobile phones, computer etc. the main function of the inverter is to convert DC to AC and step-up transformer is used to create main voltages from resulting AC.

1.2.BLOCK DIAGRAM OF INVERTER:

In the block diagram battery supply is given to the MOSFET driver where it will convert DC to AC and the resulting AC is given to the step up transformer from the step up transformer we will the get the original voltage.

CIRCUIT DIAGRAM:

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1.3.COMPONENTS LIST:

1. Resistors

2. Capacitors

3. Variable resistors

4. IC1CD4047.

5. IRF540 MOSFET.

6. LED.

7. 1N4007 Diode

8. Transformer.

9. 12V Supply.

10.Bread board.

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CHAPTER-2

2. COMPONENTS DESCRIPTION:

2.1.RESISTOR:

A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element.The current through a resistor is in direct proportion to the voltage across the resistor's terminals. This relationship is represented by Ohm's law:

Where I is the current through the conductor in units of amperes, V is the potential difference measured across the conductor in units of volts, and R is the resistance of the conductor in units of ohms.

RESISTANCE:

The ratio of the voltage applied across a resistor's terminals to the intensity of current in the circuit is called its resistance, and this can be assumed to be a constant (independent of the voltage) for ordinary resistors working within their ratings.

WORKING OF RESISTOR:

Working of a resistor can be explained with the similarity of water flowing through a pipe. Consider a pipe through which water is allowed to flow. If the diameter of the pipe is reduced, the water flow will be reduced. If the force of the water is increased by increasing the pressure, then the energy will be dissipated as heat. There will also be an enormous difference in pressure in the head and tail ends of the pipe. In this example, the force applied to the water is similar to the current flowing through the resistance. The pressure applied can be resembled to the voltage.

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RESISTOR COLOUR CODING:

 

A 2.26 kilo-ohm, 1% precision resistor with 5 color bands (E96 series), from top 2-2-6-1-1; the last two brown bands indicate the multiplier (x10), and the 1% tolerance. The larger gap before the tolerance band is somewhat difficult to distinguish.

To distinguish left from right there is a gap between the C and D bands.

band A is first significant figure of component value (left side) band B is the second significant figure (Some precision resistors have a third significant

figure, and thus five bands.) band C is the decimal multiplier band D if present, indicates tolerance of value in percent (no band means 20%)

For example, a resistor with bands of yellow, violet, red, and gold will have first digit 4 (yellow in table below), second digit 7 (violet), followed by 2 (red) zeros: 4,700 ohms. Gold signifies that the tolerance is ±5%, so the real resistance could lie anywhere between 4,465 and 4,935 ohms.

Resistors manufactured for military use may also include a fifth band which indicates component failure rate (reliability); refer to MIL-HDBK-199 for further details.

Tight tolerance resistors may have three bands for significant figures rather than two, or an additional band indicating temperature coefficient, in units of ppm/K.

All coded components will have at least two value bands and a multiplier; other bands are optional.

The standard color code per EN 60062:2005 is as follows:

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ColorSignificant

figuresMultiplier Tolerance

Temp. Coefficient (ppm/K)

Black 0 ×100 – 250 U

Brown 1 ×101 ±1% F 100 S

Red 2 ×102 ±2% G 50 R

Orange 3 ×103 – 15 P

Yellow 4 ×104 (±5%) – 25 Q

Green 5 ×105 ±0.5% D 20 Z

Blue 6 ×106 ±0.25% C 10 Z

Violet 7 ×107 ±0.1% B 5 M

Gray 8 ×108 ±0.05% (±10%)

A 1 K

White 9 ×109 – –

Gold – ×10-1 ±5% J –

Silver – ×10-2 ±10% K –

None – – ±20% M –

1. Any temperature coefficent not assigned its own letter shall be marked "Z", and the coefficient found in other documentation.

2. For more information, see EN 60062.3. Yellow and Gray are used in high-voltage resistors to avoid metal

particles in the lacquer.[3]

2.2.CAPACITOR:

A capacitor is an electronic device that is used to store electrical energy. They are only used to store the electrons and they are not capable of producing them.

CAPACITANCE:

There are mainly two concepts for defining capacitance. They are

ELECTRICAL CONCEPT:

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Capacitance is said to be the capacitor’s storage potential. In other words, for an existing potential difference or voltage “V” across the plates, the capacitance is said to be the amount of charge “Q” stored in between plates.

Capacitance (C) = Q/V.

Where Q = charge stored in between two plates

V= voltage across two plates

PHYSICAL CONCEPT:

Capacitance is defined by the physical characteristics of the two plates, such that the capacitance is equal to ratio between the square area of a plate and the distance between the plates multiplied by the dielectric of the material in between the plates.

CAPACITANCE (C) = (A/d) E

Where A= area between two plates

d= distance between two plates

E= permittivity of dielectric medium

UNITS FOR CAPACITANCE: FARADAY

WORKING OF CAPACITOR:

A capacitor consists of two metal plates which are separated by a non-conducting substance or dielectric. Take a look at the figure given below to know about dielectric in a capacitor.

Though any non-conducting substance can be used as a dielectric, practically some special materials like porcelain, Mylar, Teflon, mica, cellulose and so on. According to the size and type of dielectric used, the capacitor can be used for high voltage as well as low voltage applications. For application in radio tuning circuit’s air is commonly used as the dielectric.

For applications in timer circuits Mylar is used as the dielectric.

For high voltage applications glass is used as the dielectric.

For application in X-Ray and MRI machines ceramic is used as the dielectric.

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ADVANTAGES OF CAPACITOR:

Since the capacitor can discharge in a fraction of a second, it has a very large advantage. Capacitors are used for appliances which require high speed use like in camera flash and laser techniques.

Capacitors are used to remove ripples by removing the peaks and filling in the valleys.

A capacitor allows ac voltage to pass through and blocks dc voltage. This has been used in many electronic applications.

2.3.VARIABLE RESISTOR:

An electronic component that is used to vary the amount of current that flows through a circuit. It works by sliding a wiper terminal across a resistive material, typically a thin film or chunk of carbon or a resistive wire made of nickel chromium or tungsten alloys. After being set to the appropriate location, the wiper's position often remains fixed on the circuit board; however, it can also be made user adjustable with a screwdriver.

2.4.SIMPLE ASTABLE MULTIVIBRATOR

IC CD4047:CD4047 is a multi vibrator with very low power consumption designed by TEXAS INSTRUMENTS.it can operate in monostable multivibrator and also astable multivibrator.in the astable multivibrator mode it can operate in free ruMUnning or gatable modes and also provides good astable frequency stability. It can generate 50% duty cycle which will create a pulse, which can be applied for inverter circuit. This is mainly used in frequency discriminators, timing circuits frequency divisions etc.

When we say to the an astable multivibrator circuit, Many people will think to Many people think of as the most IC-555. But this time, it is recommended circuit in Figure 1. Which use IC-4047 CMOS with ability of this nature as well. And the advantage is, That output will be a square wave, which has three forms are: First at pin 13 of IC1 will be basic frequency, Second is pin 11 will be Is half that of basic frequencies, And thirdly at pin 10 is half the

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frequency of basic frequency. but will has to invert the signal to 180 degrees. So is there a characteristics opposite to the second output.

Figure 1 the Simple astable multivibrator circuit using CD4047 Cmos ICThis circuit yet cannot adjust duty cycle. So sorry, if one were to try to use the adjusted duty cycle. But output of IC will have duty cycle of 50% makes has symmetry exists. For the controller frequency will be serves as VR1 and C1. By the value of VR1 is used in a range of 1 KHz to 1 MHz. To Adjust to the desired frequency. The C1 will determine the frequency. The value used to determine the various range. Can see from the table below. And should select capacitors that have low leakage.To waveform distortion and frequency can not be much.

The value of C1 in circuit as Figure 1 to determine the frequency use.1uF = 1-10Hz0.1uF = 10Hz-1kHz0.01uF = 100Hz-10kHz

How to buildsThis project is a few components so can put on the universal PCB board as Figure 2. And be carefully for wiring,the polarity of the electrolytic capacitors, Pin of the IC.

Figure 2 the components layout of this projectsComponents listThe potentiometerVR1______See in textCapacitorsC1_______See in textSemiconductorIC1______CD4047____Low Power Monostable Astable MultivibratorOther componentsSocket 14 pin, The universal PCB board.

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2.5.MOSFET:

IRF540: IRF540 is a N-channel enhanced mode silicon gate field effect transistor (MOSFET).they are mainly used in switching regulators, switching converters relay drivers etc. the reason for using them in the INVERTER circuit is the because it is a high switching transistor , can work in very low gate drive power and have high input impedance.

IRF540 Symbol:

Basic Structure and Principle of Operation

The n-type Metal-Oxide-Semiconductor Field-Effect-Transistor (MOSFET) consists of a source and a drain, two highly conducting n-type semiconductor regions which are isolated from the p-type substrate by reversed-biased p-n diodes. A metal (or poly-crystalline) gate covers the region between source and drain, but is separated from the semiconductor by the gate oxide. The basic structure of an n-type MOSFET and the corresponding circuit symbol are shown in figure .

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 Crosssection and circuit symbol of an n-type Metal-Oxide-Semiconductor-Field-Effect-Transistor (MOSFET)

As can be seen on the figure the source and drain regions are identical 1. It is the applied voltages which determine which n-type region provides the electrons and becomes the source, while the other n-type region collects the electrons and becomes the drain. The voltages applied to the drain and gate electrode as well as to the substrate by means of a back contact are refered to the source potential, as also indicated on the figure.

A top view of the same MOSFET is shown in Fig. 7.1.2, where the gate length, L, and gate width, W, are identified. Note that the gate length does not equal the physical dimension of

the gate, but rather the distance between the source and drain regions underneath the gate. The overlap between the gate and the source and drain region is required to ensure that the inversion layer forms a continuous conducting path between the source and drain region.

Typically this overlap is made as small as possible in order to minimize its parasitic

The flow of electrons from the source to the drain is controlled by the voltage applied to the gate. A positive voltage applied to the gate, attracts electrons to the interface between the gate dielectric and the semiconductor. These electrons form a conducting channel between the source and the drain, called the inversion layer. No gate current is required to maintain the inversion layer at the interface since the gate oxide blocks any carrier flow. The net result is that the current between drain and source is controlled by the voltage which is applied to the gate.

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The typical current versus voltage (I-V) characteristics of a MOSFET are shown in the figure below. Implemented is the quadratic model for the MOSFET.

 mosfetiv.xls - mosfetiv.gif

Fig.7.1.3 I-V characteristics of an n-type MOSFET with VG = 5 V (top curve), 4 V, 3 V and 2 V (bottom curve)

NOTE: We will primarily discuss the n-type or n-channel MOSFET. This type of MOSFET is fabricated on a p-type semiconductor substrate. The complementary MOSFET is the p-type or p-channel MOSFET. It contains p-type source and drain regions in an n-type substrate. The inversion layer is formed when holes are attracted to the interface by a negative gate voltage. While the holes still flow from source to drain, they result in a negative drain current. CMOS circuits require both n-type and p-type devices.

2.6.LIGHT EMITTING DIODE

Basically, LEDs are just tiny light bulbs that fit easily into an electrical circuit. But unlike ordinary incandescent bulbs, they don't have a filament that will burn out, and they don't get especially hot. They are illuminated solely by the movement of electrons in a semiconductor material, and they last just as long as a standard transistor.

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Light emitting diodes, commonly called LED’s are real unsung heroes in the electronics world. They do dozens of different jobs and are found in all kinds of devices.

PIN DIAGRAM OF LED:

WORKING OF LED:

In the case of LEDs, the conductor material is typically aluminum-gallium-arsenide (Al Ga As). In pure aluminum-gallium-arsenide, all of the atoms bond perfectly to their neighbors, leaving no free electrons (negatively-charged particles) to conduct electric current. In doped material, additional atoms change the balance, either adding free electrons or creating holes where electrons can go. Electrons can jump from hole to hole, moving from a negatively-charged area to a positively-charged area.

A diode comprises a section of N-type material bonded to a section of P-type material, with electrodes on each end. This arrangement conducts electricity in only one direction. When no voltage is applied to the diode, electrons from the N-type material fill holes from the P-type material along the junction between the layers, forming a depletion zone. In a depletion zone, the semiconductor material is returned to its original insulating state -- all of the holes are filled, so there are no free electrons or empty spaces for electrons, and charge can't flow.

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APPLICATIONS:

LED’s form the numbers on digital clocks. LED’s transmit the information from remote controls. LED’s light up watches and tell you when your appliances are turned on. LED’s collected together; they can form images on jumbo television screen or

illuminate a traffic light.

2.7.P-N DIODE

A p–n diode is a type of two-terminal semiconductor diode based upon the p–n junction that conducts current in only one direction, made by joining a p-type semiconducting layer to an n-type semiconducting layer.

The figure shows two of the many possible structures used for p–n semiconductor diodes, both adapted to increase the voltage the devices can withstand in reverse bias. The top structure uses a mesa to avoid a sharp curvature of the p+-region next to the adjoining n-layer. The bottom structure uses a lightly doped p-guard-ring at the edge of the sharp corner of the p+-layer to spread the voltage out over a larger distance and reduce the electric field.

OPERATION OF DIODE:

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Here, the operation of the abrupt p–n diode is considered. By "abrupt" is meant that the p- and n-type doping exhibit a step function discontinuity at the plane where they encounter each other. The objective is to explain the various bias regimes in the figure displaying current-voltage characteristics. Operation is described using band-bending diagrams that show how the lowest conduction band energy and the highest valence band energy vary with position inside the diode under various bias conditions. For additional discussion, see the articles Semiconductor and Band diagram.

V-I CHARACTERISTICS OF P-N DIODE

ADVANTAGES:

1. It is cheaper and easy to use.2. It is basically an electrically controlled variable capacitor no moving parts need a

monitored voltage source to hold the value temperature sensitive Si based don’t work over 100 degrees Celsius variable capacitor.

3. Low power consumption, simplicity, high speed.4. Low noise.5. It has high frequency.6. Low power dissipation.

2.8.TRANSFORMER

A transformer is an electrical device that transfers energy between two circuits through electromagnetic induction. A transformer may be used as a safe and efficient voltage converter to change the AC voltage at its input to a higher or lower voltage at its output.

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Other uses include current conversion, isolation with or without changing voltage and impedance conversion.

A transformer most commonly consists of two windings of wire that are wound around a common core to provide tight electromagneticcoupling between the windings. The core material is often a laminated iron core. The coil that receives the electrical input energy is referred to as the primary winding, the output coil is the secondary winding

Step Up Transformer:

A step-up transformer is one whose secondary voltage is greater than its primary voltage. This kind of transformer "steps up" the voltage applied to it. For instance, a step up transformer is needed to use a 220v product in a country with a 110v supply.Step Down Transformer:Its the opposite of the above, and would be used to run for example a 110v product in a country with a 220v mains supply.

APPLICATIONSTransformers perform voltage conversion, isolation protection, and impedance matching. In terms of voltage conversion, transformers can step up voltage and step down current from generators to high voltage transmission lines, and step down

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voltage/step up current to local distribution circuits or industrial customers. The step-up transformer is used to increase the secondary voltage relative to the primary voltage. The step-down transformer is used to decrease the secondary voltage relative to the primary voltage. Transformers range in size from thumbnail-sized units used in microphones to those weighing hundreds of tons interconnecting the power grid. A broad range of transformer designs are used in electronic and electric power applications, including miniature, audio, isolation, high-frequency, power conversion, etc.

2.9.SWITCH:

A power symbol is a symbol indicating that a control activates or deactivates a particular device. It incorporates line and circle figures, with the arrangement informed by the function

of the control. The universal power symbols are described in the International Electrotechnical Commission 60417 standard, Graphical symbols for use on equipment,

appearing in the 1973 edition of the document (as IEC 417) and informally used earlier.

.

2.10BATTERY:

An electric battery is a device consisting of one or more electrochemical cells that convert stored chemical energy into electrical energy. Each cell contains a positive terminal, or cathode, and a negative terminal, or anode. Electrolytes allow ions to move between the electrodes and terminals, which allows current to flow out of the battery to perform work.

Primary (single-use or "disposable") batteries are used once and discarded; the electrode materials are irreversibly changed during discharge. Common examples are the alkaline battery used for flashlights and a multitude of portable devices. Secondary (rechargeable batteries) can be discharged and recharged multiple times; the original composition of the electrodes can be restored by reverse current. Examples include the lead-acid batteries used in vehicles and lithium ion batteries used for portable electronics. Batteries come in many shapes and sizes, from miniature cells used to power hearing aids and wristwatches to battery

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banks the size of rooms that provide standby power for telephone exchanges and computer data centers.

2.11.BREAD BOARD

A breadboard (proto board) is a construction base for prototyping of electronics. The term is commonly used to refer to solder less, breadboard (plug board).

Because the solder less breadboard does not require soldering, it is reusable. This makes it easy to use for creating temporary prototypes and experimenting with circuit design. Older breadboard types did not have this property. A strip board (Vero board) and similar prototyping printed circuit boards, which are used to build permanent soldered prototypes or one-offs, cannot easily be reused. A variety of electronic systems may be prototyped by using breadboards, from small analog and digital circuits to complete central processing units (CPUs).

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CHAPTER-3

3.1.CONSTRUCTION OF INVERTER:

Here is the circuit diagram of a simple 100 watt inverter using IC CD4047 and MOSFET IRF540. The circuit is simple low cost and can be even assembled on a veroboard.

CD 4047 is a low power CMOS astable/monostable multivibrator IC. Here it is wired as an astable multivibrator producing two pulse  trains of 0.01s which are 180 degree out of phase at the pins 10 and 11 of the IC. Pin 10 is connected to the gate of Q1 and pin 11 is connected to the gate of Q2. Resistors R3 and R4 prevents the loading of the IC by the respective MOSFETs. When pin 10 is high Q1 conducts and  current flows through the upper half of the transformer primary which accounts for the positive half of the output AC voltage.

When pin 11 is high Q2 conducts and  current flows through the lower half of the transformer primary in opposite direction and it accounts for the negative half of the output AC voltage.

CIRCUIT DIAGRAM:

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3.2.WORKING OF 100W INVERTER :

In the circuit diagram we can observe that 12V battery is connecter to the diode LED

and also connected to the pin8 of the IC 4047 which is VCC or power supply pin and also to

pin 4 and 5 which are astable and  complement astable of  the IC. Diode in the circuit will

help not give any reverse current, LED will work as a indicator to the battery is working or

not.

 IC CD4047 will work in the astable multivibrator mode. To work it in astable

multivibrator mode we need an external capacitor which should be connected between the

pin1 and pin3. Pin2 is connected by the resistor and a variable resistor to change the change

the output frequency of the IC. Remaining pins are grounded .The pins 10 and 11 are

connected to the gate of the mosfets IRF540. The pin 10 and 11 are Q and ~Q from these pins

the output frequencies is generated with 50% duty cycle.

The output frequency is connected to the mosfets through resistor which will help to

prevent to the loading of the mosfets. The main AC current is generated by the two mosfets

which will act as a two electronic switches. The battery current is made to flow upper half or

positive half of the primary coil of transformer through Q1 this is done when the pin 10

becomes high and lower half or negative half is done by opposite current flow through the

primary coil of transformer, this is done when pin 11 is high. By switching the two mosfets

current is generated.

This AC is given to the step up transformer of the secondary coil from this coil only

we will get the increased AC voltage , this AC voltage is so high; from step up transformer we

will get the max voltage. Zenor diode will help avoid the reverse current.

NOTE: The generated AC is not equal to the normal AC mains or house hold current. You cannot use this voltage for pure electric appliances like heater, electric cooker etc. Because of the fast switching of mosfets heat is dissipated which will effect the efficiency, use heat sink to remove this problem.

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CHAPTER-4

4.1.APPLICATIONS:

Home appliances

Small scale industries

Vehicles

4.2.CONCLUSION:

It is concluded that simple 100w inverter mainly used in home appliences,automobiles.

4.3.REFERENCE:

www.electronics4u.com

www.circuitstoday.com

www.eleccircuit.com

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