Proteus lab Manual.pdf

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Department of Electronics Engg., P.V.P.I.T., Budhgaon

Budhgaon-416304

Department of Electronics Engineering

Circuit Simulation

LAB MANUAL

Prepared by

Prof. K. P. Paradeshi

Associate Professor, Electronics Engineering, [email protected]

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Dr. V. P. Shetkari Shikshan Mandal’s

Padmabhooshan Vasantraodada Patil Institute of Technology,

Budhgaon-416304

Department of Electronics Engineering

Circuit Simulation

Experiment No. : 01 Name of Experiment: Roll Number : Date Performed : Date Checked : Signature (Batch In-charge)

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Department of Electronics Engg., P.V.P.I.T., Budhgaon Aim:

Design & stimulate the half wave rectifier.

Objectives:

• To understand principal of working of Half Wave Rectifier circuit. • To understand the circuit arrangement of Half Wave Rectifier circuit.

• To understand the simulation procedure of ―Half Wave Rectifier‖ circuit using proteus.

• To observe & analyze the output waveforms

Outcomes:

• Able to understand principal of working of Half Wave Rectifier circuit. • Able to understand the circuit arrangement of Half Wave Rectifier circuit. • Able to understand the simulaton procedure of Half Wave Rectifier circuit

using proteus.

• Able to observe & analyse the circuit.

Programme Education Objective (PEO) Satisfied : 2,3

• To enable student to analyse solve electronics engineering problem by applying basic principles of mathematics , sciences and engineering and also be able to use modern engineering techniques , skills and tools to fulfill social needs. • To enable to innovate, design and develop a variety of electronic and computer

based components and system for applications including signal processing , communication , computer network and control system.

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Department of Electronics Engg., P.V.P.I.T., Budhgaon Introduction:

The device which converts ac voltage into dc voltage is called rectifiers. In fact, rectifiers produce unidirectional & pulsating voltage from ac source.

Rectifiers offers a low resistance to the flow of current in one direction & high resistance to flow of current in opposite direction that is rectifier converts AC into DC. This conversion is achieved by rectifier supplied with AC signal using step down transformer. The output of contains pulsating DC (ripple voltage) which can be removed by using filter circuit. we have to design the HWR using proteus. It is easy to design on the proteu

Circuit Diagram:

Half wave rectifier

Circuit arrangement:

The circuit arrangement of half wave as shown in fig. It uses one transformer for providing step down operation as well as to provide electrical isolation. In this type of arrangement diode D, load resistance RL are used, the output is taken across load resistance as shown in figure.

Theory:

When a single rectifier unit is placed in series with the load across an ac supply, it converts alternating voltage into uni-directional pulsating voltage, using one half cycles of the applied voltage, the other half cycles being suppressed because it conducts only in one direction. Unless there is an inductance or battery in the circuit, the current will be zero, therefore, for half the time. This is called half-wave rectification. As already discussed, diode

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provides the unilateral conduction necessary for rectification. This is true for diodes of all types-vacuum, gas-filled, crystal or semiconductor, metallic (copper oxide and selenium types) diodes. Semiconductor diodes, because of their inherent advantages are usually used as a rectifying device. However, for very high voltages, vacuum diodes may be employed. The half-wave rectifier circuit using a semiconductor diode with a load resistance RL

but no smoothing filter is given in figure. The diode is connected in series with the secondary of the transformer and the load resistance RL, the primary of the transformer is being

connected to the ac supply mains.

A transformer has been added to provide the desired voltage into the rectifier. For high voltage DC power supplies this would obviously be a step-up transformer,but with many solid-state equipment application voltages of 4.5,6,9,22.5,40volts are used. Thus necessitating

a step-down transformer. Hence,in HWR the step-down transformer is used.

Working of a Half wave rectifier:

The ac voltage across the secondary winding changes polarities after every half cycle. During the positive half-cycles of the input ac voltage i.e. when upper end of the secondary winding is positive w.r.t. its lower end, the diode is forward biased and therefore conducts current. When forward voltages crosses barrier potential (0.7v for silicon diode) the diode works as closed switch,the large current flows through RL.This current produces dc voltage across the load RL. If the forward resistance of the diode is assumed to be zero (in practice, however, a small resistance exists) the input voltage during the positive half-cycles is directly applied to the load resistance RL, making its upper end positive w.r.t. its lower end. The

waveforms of the output current and output voltage are of the same shape as that of the input ac voltage.

During the negative half cycles of the input ac voltage i.e. when the lower end of the secondary winding is positive w.r.t. its upper end, the diode is reverse biased and so does not conduct that is diode D acts as open switch.Thus during the negative half cycles of the input ac voltage the current through and voltage across the load remains zero if the reverse current, being very small in magnitude, is neglected. Thus for the negative half cycles no power is delivered to the load.

Thus the output voltage developed across load resistance RL (VL) is a series of positive

half cycles of alternating voltage, with intervening very small constant negative voltage levels, It is obvious from the figure that the output is not a steady dc, but only a pulsating dc wave. Since only half-cycles of the input wave are used, it is called a half-wave rectifier. The output voltage is unidirectional,pulsating & intermittent.

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Department of Electronics Engg., P.V.P.I.T., Budhgaon DC OUTPUT VOLTAGE:-

Vdc = Vm/3.14 (with no load) Vm= maximum voltage

DC OUTPUT CURRENT:-

Idc = Im/3.14 Im=maximum current

Significance of half wave rectifier using proteus:

The most important characteristics which are required to be specified for a power supply are given below :

1. The required output dc voltage.

2. The average and peak currents in the diode. 3. The peak inverse voltage (PIV) of each diode. 4. The regulation.

5. The ripple factor

Advantages:

• Simple circuit and low cost.

Disadvantages:

• The output current in the load contains, in addition to dc component, ac components of basic frequency equal to that of the input voltage frequency. Ripple factor is high and an elaborate filtering is, therefore, required to give steady dc output.

• The power output and, therefore, rectification efficiency is quite low. This is due to the fact that power is delivered only half the time.

• Transformer utilization factor is low.

• DC saturation of transformer core resulting in magnetizing current and hysteresis losses and generation of harmonics.

The type of supply available from a half-wave rectifier is not satisfactory for general power supply. This type of supply can be satisfactory for some particular purposes such as battery charging.

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1. From main page of Proteus, click on ‗P‘ to pick device from library.

2. In pick device, insert the component which has to be selected & click on ‗OK‘. 3. Place the all components on the Proteus screen.

4. Right click and select edit properties to change the values. 5. Add voltage probe at input and output.

6. Select the ‗graph mode‘& choose analouge Analysis graph window. 7. Right click and select ‗add traces‘ (input & output trace).

8. Right click & activate simulation graph.

9. Observe and analyse input & output waveforms.

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Department of Electronics Engg., P.V.P.I.T., Budhgaon Conclusion:

By using Proteus we can understand working of half wave rectifier. During the negative half cycles of the input ac voltage, diode D acts as open switch. Thus for the negative half cycles no power is delivered to the load. The input voltage during the positive half-cycles is directly applied to the load resistance RL and waveforms appears across diode

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Padmabhooshan Vasantraodada Patil Institute of Technology,

Budhgaon-416304

Department of Electronics Engineering

Circuit Simulation

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Department of Electronics Engg., P.V.P.I.T., Budhgaon Title:

To study bridge full wave rectifier.

Aim:

To design and simulate bridge full wave rectifier circuit using proteus and observe the

waveforms.

Objectives:

• To understand principal of working of bridge full wave rectifier. • To understand the circuit arrangement of bridge full wave rectifier.

• To understand the simulation procedure of bridge full wave rectifier circuit using proteus.

• To observe & analyze the output waveforms

Outcomes:

• Able to understand principal of working of bridge FWR circuit. • Able to understand the circuit arrangement of bridge FWR circuit.

• Able to understand the simulation procedure of bridge FWR circuit using Proteus.

• Able to observe & analyze the circuit.

Programme Education Objective (PEO) Satisfied: 2,3

• To enable student to analyse solve electronics engineering problem by applying basic principles of mathematics , sciences and engineering and also be able to use modern engineering techniques , skills and tools to fulfill social needs. • To enable to innovate, design and develope a variety of electronic and computer

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Department of Electronics Engg., P.V.P.I.T., Budhgaon The Full Wave Bridge Rectifier

Another type of circuit that produces the same output waveform as the full wave rectifier circuit above is that of the Full Wave Bridge Rectifier. This type of single phase rectifier uses four individual rectifying diodes connected in a closed loop "bridge" configuration to produce the desired output. The main advantage of this bridge circuit is that it does not require a special centre tapped transformer, thereby reducing its size and cost. The single secondary winding is connected to one side of the diode bridge network and the load to the other side as shown below.

Working of full wave bridge rectifier:

The circuit arrangement made for bridge FWR is as shown in fig. It uses one transformer for providing step down operation as well as to provide electrical isolation. In this type of arrangement, four diodes (D1, D2,D3,D4) are connected in such a way , to form a bridge. Hence it is called as ―bridge FWR‖. Here, two diodes are conducting at a time and remaining two diodes are non-conducting. The output is taken across load resistance as shown in fig.

During positive half cycle of AC input, the diode D1 and D3 becomes forward bias, at the same time, diodes D2 and D4 becomes reverse bias. Thus, current flows through the path : diode D1, load resistance RL , diode D3, to the second end of transformer‘s secondary winding. In this situation, current through RL flows from top to bottom producing positive output voltage across it.

During negative half cycle of AC input, diode D2 and D4 becomes forward biased, at the same time, diodes D1 and D3 becomes reverse bias. Thus, current flows through the path : diode D2, load resistance RL , diode D4, to the second end of transformer‘s secondary winding. In this situation, current flows in the same direction producing positive output voltage across load resistance as shown in waveforms.

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Department of Electronics Engg., P.V.P.I.T., Budhgaon Theory:.

The Diode Bridge Rectifier

The four diodes labelled D1 to D4 are arranged in "series pairs" with only two

diodes conducting current during each half cycle. During the positive half cycle of the supply, diodes D1 and D2 conduct in series while diodes D3 and D4 are reverse biased and the current flows through the load as shown below.

The Positive Half-cycle

During the negative half cycle of the supply, diodes D3 and D4 conduct in series, but diodes D1 and D2 switch "OFF" as they are now reverse biased. The current flowing through the load is the same direction as before.

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As the current flowing through the load is unidirectional, so the voltage developed across the load is also unidirectional the same as for the previous two diode full-wave rectifier, therefore the average DC voltage across the load is 0.637Vmax. However in

reality, during each half cycle the current flows through two diodes instead of just one so the amplitude of the output voltage is two voltage drops ( 2 x 0.7 = 1.4V ) less than the input VMAX amplitude. The ripple frequency is now twice the supply frequency (e.g. 100Hz for a

50Hz supply). Although we can use four individual power diodes to make a full wave bridge rectifier, pre-made bridge rectifier components are available "off-the-shelf" in a range of different voltage and current sizes that can be soldered directly into a PCB circuit board or be connected by spade connectors.The image to the right shows a typical single phase bridge rectifier with one corner cut off. This cut-off corner indicates that the terminal nearest to the corner is the positive or +ve output terminal or lead with the opposite (diagonal) lead being the negative or -ve output lead. The other two connecting leads are for the input alternating voltage from a transformer secondary winding.

The Smoothing Capacitor

We saw in the previous section that the single phase half-wave rectifier produces an output wave every half cycle and that it was not practical to use this type of circuit to produce a steady DC supply. The full-wave bridge rectifier however, gives us a greater mean DC value (0.637 Vmax) with less superimposed ripple while the output waveform is twice that of the frequency of the input supply frequency.

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Department of Electronics Engg., P.V.P.I.T., Budhgaon Full-wave Rectifier with Smoothing Capacitor

The smoothing capacitor converts the full-wave rippled output of the rectifier into a smooth DC output voltage. Generally for DC power supply circuits the smoothing capacitor is an Aluminum Electrolytic type that has a capacitance value of 100uF or more with repeated DC voltage pulses from the rectifier charging up the capacitor to peak voltage. However, there are two important parameters to consider when choosing a suitable smoothing capacitor and these are its Working Voltage, which must be higher than the no-load output value of the rectifier and its Capacitance Value, which determines the amount of ripple that will appear superimposed on top of the DC voltage.

Too low a capacitance value and the capacitor has little effect on the output waveform. But if the smoothing capacitor is sufficiently large enough (parallel capacitors can be used) and the load current is not too large, the output voltage will be almost as smooth as pure DC. As a general rule of thumb, we are looking to have a ripple voltage of less than 100mV peak to peak.

The maximum ripple voltage present for a Full Wave Rectifier circuit is not only determined by the value of the smoothing capacitor but by the frequency and load current, and is calculated as:

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Where: I is the DC load current in amps, ƒ is the frequency of the ripple or twice the input frequency in Hertz, and C is the capacitance in Farads.

The main advantages of a full-wave bridge rectifier is that it has a smaller AC ripple value for a given load and a smaller reservoir or smoothing capacitor than an equivalent half-wave rectifier. Therefore, the fundamental frequency of the ripple voltage is twice that of the AC supply frequency (100Hz) where for the half-wave rectifier it is exactly equal to the supply frequency (50Hz).

The amount of ripple voltage that is superimposed on top of the DC supply voltage by the diodes can be virtually eliminated by adding a much improved π-filter (pi-filter) to the output terminals of the bridge rectifier. This type of low-pass filter consists of two smoothing capacitors, usually of the same value and a choke or inductance across them to introduce a high impedance path to the alternating ripple component.

Another more practical and cheaper alternative is to use an off the shelf 3-terminal voltage regulator IC, such as a LM78xx (where "xx" stands for the output voltage rating) for a positive output voltage or its inverse equivalent the LM79xx for a negative output voltage which can reduce the ripple by more than 70dB (Datasheet) while delivering a constant output current of over 1 amp.

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FWR Circuit Using Proteus

Components required:

Name Description Number of

components required

RES Resistor(3.3K) 1

DIODE Diode 1N4007 4

TRAN Transformer 280-280) 1

Vac Ac voltage source 1

GND Ground 3

Procedure using proteus:

1. First of all, pick a bridge of diodes 1N4007 from the components list, and place it properly on the screen

2. Pick the transformer having rating of 12-0-12 and place it as per the circuit diagram. 3. Pick a resistance of 3.3kilo ohm, and place it properly.

4. Connect the AC Source of 230V(freq.50Hz) volts source .

5. With the help of wires, connect all these components in a proper way, as shown in fig. 6. Connect voltage probes to the input & output positions.

7. open graph option and activate analogue analysis option to observe the output waveforms.

8. By right clicking on the window, add the traces of each component. And then simulate the graph. After that, you will get desired output waveforms of the bridge FWR.

Advantages:

1.Smaller size of transformer is required due to higher value of transformer utilization factor. 2.The need of centre tap transformer is eliminated.

3.PIV rating of diode is less as compared to centre tap FWR. 4.There is no problem of transformer core saturation.

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CIRCUIT SIMULATION

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Department of Electronics Engg., P.V.P.I.T., Budhgaon Conclusion

:

By studying bridge FWR, we conclude that bridge FWR is most efficient

electronic circuit which converts AC signal into DC signal. As the current flowing through the load is unidirectional, so the voltage developed across the load is also unidirectional the same as for the previous two diode full-wave rectifier, therefore the average DC voltage across the load is 0.637Vmax. However in reality, during each half cycle the current flows through two diodes instead of just one so the amplitude of the output voltage is two voltage drops ( 2 x 0.7 = 1.4V ) less than the input VMAX amplitude. The ripple frequency is now

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Padmabhooshan Vasantraodada Patil Institute of Technology,

Budhgaon-416304

Department of Electronics Engineering

Circuit Simulation

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Department of Electronics Engg., P.V.P.I.T., Budhgaon Title :

Low Pass Filter & High Pass Filter .

Aim :

To Study & simulate frequency response of low pass & high pass filter.

Objectives:

 To understand principal of working of low pass & high pass filter.

 To understand the circuit arrangement of low pass & high pass filter.

 To understand the procedure of low pass & high pass filter using capacitor& register circuit using proteus.

 To observe the frequency response waveforms and analyze the circuit.

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Outcomes:

 Students will be able to study low pass & high pass filter using capacitor& register.

 Students will be able to understand the circuit arrangement of pass & high pass filter

 Students will be able to understand the procedure of pass & high pass filter using capacitor & register circuit using proteus.

 Students will be able to observe the simulation and analyse the working of circuit.

 To enable student to analyse solve electronics engineering problem by applying basic principles of mathematics , sciences and engineering and also be able to use modern engineering techniques , skills and tools to fulfill social needs

 To enable to innovate , design and develop a variety of electronic and computer based components and system for applications including signal processing , communication , computer network and control system.

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A low-pass filter is an electronic filter that passes low-frequency signals and attenuates (reduces the amplitude of) signals with frequencies higher than the cutoff frequency. The actual amount of attenuation for each frequency varies from filter to filter. It is sometimes called a high-cut filter, or treble cut filter when used in audio applications. A low-pass filter is the opposite of a high-pass filter. A band-pass filter is a combination of a low-pass and a high-pass.

Low-pass filters exist in many different forms, including electronic circuits (such as a hiss filter used in audio), anti-aliasing filters for conditioning signals prior to analog-to-digital conversion, analog-to-digital filters for smoothing sets of data, acoustic barriers, blurring of images, and so on. The moving average operation used in fields such as finance is a particular kind of low-pass filter, and can be analyzed with the same signal processing techniques as are used for other low-pass filters. Low-pass filters provide a smoother form of a signal, removing the short-term fluctuations, and leaving the longer-term trend.

An optical filter could correctly be called low-pass, but conventionally is described as "longpass" (low frequency is long wavelength), to avoid confusion.

Electronic low-pass filters

Passive electronic realization

Passive, first order low-pass RC filter

One simple electrical circuit that will serve as a low-pass filter consists of a resistor in series with a load, and a capacitor in parallel with the load. The capacitor exhibits reactance, and blocks low-frequency signals, causing them to go through the load instead. At higher frequencies the reactance drops, and the capacitor effectively functions as a short circuit. The combination of resistance and capacitance gives the time constant of the filter

(represented by the Greek letter tau). The break frequency, also called the turnover frequency or cutoff frequency (in hertz), is determined by the time constant:

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Department of Electronics Engg., P.V.P.I.T., Budhgaon or equivalently (in radians per second):

One way to understand this circuit is to focus on the time the capacitor takes to charge. It takes time to charge or discharge the capacitor through that resistor:

At low frequencies, there is plenty of time for the capacitor to charge up to practically the same voltage as the input voltage.

At high frequencies, the capacitor only has time to charge up a small amount before the input switches direction. The output goes up and down only a small fraction of the amount the input goes up and down. At double the frequency, there's only time for it to charge up half the amount.

Another way to understand this circuit is with the idea of reactance at a particular frequency: Since DC cannot flow through the capacitor, DC input must "flow out" the path marked

(analogous to removing the capacitor).

Since AC flows very well through the capacitor — almost as well as it flows through solid wire — AC input "flows out" through the capacitor, effectively short circuiting to ground (analogous to replacing the capacitor with just a wire).

The capacitor is not an "on/off" object (like the block or pass fluidic explanation above). The capacitor will variably act between these two extremes. It is the Bode plot and frequency response that show this variability.

Active electronic realization

An active low-pass filter Another type of electrical circuit is an active low-pass filter.

In the operational amplifier circuit shown in the figure, the cutoff frequency (in hertz) is defined as:

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Department of Electronics Engg., P.V.P.I.T., Budhgaon or equivalently (in radians per second):

The gain in the passband is −R2/R1, and the stopband drops off at −6 dB per octave (that is

−20 dB per decade) as it is a first-order filter.

Discrete-time realization

Many digital filters are designed to give low-pass characteristics. Both infinite impulse response and finite impulse response low pass filters as well as filters using fourier transforms are widely used.

Simple infinite impulse response filter

The effect of an infinite impulse response low-pass filter can be simulated on a computer by analyzing an RC filter's behavior in the time domain, and then discretizing the model.

A simple low-pass RC filter

Finite impulse response

Finite impulse response filters can be built that approximate to the ideal sinc time domain response. In practice the time domain response must be time truncated and is often of a simplified shape; in the simplest case, a running average can be used giving a square time response.[3]

High Pass Filter

A high-pass filter (HPF) is an electronic filter that passes high-frequency signals but attenuates (reduces the amplitude of) signals with frequencies lower than the cutoff frequency. The actual amount of attenuation for each frequency varies from filter to filter. A high-pass filter is usually modeled as a linear time-invariant system. It is sometimes called a low-cut filter or bass-cut filter.[1]

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High-Department of Electronics Engg., P.V.P.I.T., Budhgaon

pass filters have many uses, such as blocking DC from circuitry sensitive to non-zero average voltages or RF devices. They can also be used in conjunction with a low-pass filter to make a bandpass filter.

First-order continuous-time implementation

Figure 1: A passive, analog, first-order high-pass filter, realized by an RC circuit

The simple first-order electronic high-pass filter shown in Figure 1 is implemented by placing an input voltage across the series combination of a capacitor and a resistor and using the voltage across the resistor as an output. The product of the resistance and capacitance (R×C) is the time constant (τ); it is inversely proportional to the cutoff frequency fc, that is,

where fc is in hertz, τ is in seconds, R is in ohms, and C is in farads.

Figure 2: An active high-pass filter

Figure 2 shows an active electronic implementation of a first-order high-pass filter using an operational amplifier. In this case, the filter has a passband gain of -R2/R1 and has a corner frequency of

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Because this filter is active, it may have non-unity passband gain. That is, high-frequency signals are inverted and amplified by R2/R1.

Advantages:

Low pass filter

1. The gain of integrater decreases with frequency whereas gain of differentiator increases linearly with frequency,so it is easier to stabilize the output of integrators.

2. Due to limited B.W,integrator are less sensitive to noise voltage than differentiators. 3.It is more convenient to introduce the initial conditions in an integrator circuit.

Disadvantages:

For lower frequency reactance offered by capacitor C is very high & hence these frequencies are not passed at output.

Low pass filter circuit using proteus:

Procedure using Proteus:

15. Select the ‗graph mode‘ & choose analouge Analysis graph window. 16. Right click and select ‗add traces‘(input & output trace).

18. Observe and analyse input & output waveforms.

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High pass filter using proteus

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Department of Electronics Engg., P.V.P.I.T., Budhgaon Low pass filter using proteus:

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we can observe simulation of circuit & analyses the waveform taken across capacitor C1.

In Low pass filter the frequency is passes below cut off region And in high pass filter the frequency passes above the cut off region.

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Padmabhooshan Vasantraodada Patil Institute of Technology,

Budhgaon-416304

Department of Electronics Engineering

Circuit Simulation

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Design and simulate the ± 5V and ±12V regulated power Supply.

Objectives:

 To understand principal of working of regulated power supply.

 To understand the circuit arrangement regulated power supply.

 To understand the procedure of regulated power supply circuit using proteus.

 To observe the simulation of circuit.

Outcomes:

 Able to understand principal of working of regulated power supply circuit.

 Able to understand the circuit arrangement of regulated power supply circuit.

 Able to understand the procedure of regulated power supply.‖ circuit using proteus.

 Able to observe the simulation of circuit.

• To enable student to analyse solve electronics engineering problem by applying basic principles of mathematics , sciences and engineering and also be able to use modern engineering techniques , skills and tools to fulfill social needs.

• To enable to innovate, design and develop a variety of electronic and computer based components and system for applications including signal processing , communication , computer network and control system.

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Department of Electronics Engg., P.V.P.I.T., Budhgaon Principle:

7805 is a 5V fixed three terminal positive voltage regulator IC. The IC has features such as safe operating area protection, thermal shut down, internal current limiting which makes the IC very rugged. Output currents up to 1A can be drawn from the IC provided that there is a proper heat sink. A 9V transformer steps down the main voltage, 1A bridge rectifies it and capacitor C1 filters it and 7805 regulates it to produce a steady 5voltDC.

Introduction:

The stepdown transformer, down-converts the high voltage AC input (230V,50Hz) to a 9V,2A; because the transformer we used here having a specification of 9V/A. The alternating voltage from secondary terminal of the transformer is given to a bridge rectifier. The bridge rectifier converts alternating voltage to unidirectional voltage with the switching action of diodes. This voltage is finally fed to a 5V regulator IC through a 470uF,50v electrolytic capacitor, which eliminates the ripples and make the output stable. After regulation we get a 5V DC voltage at the output of 7805 IC.

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+5V output . In this type of arrangement two resistors and two capacitors are used, the output is taken across pin no 3 of IC 555 as shown in figure.

Theory:

Theory of IC 78XX Transformer:-

A bridge rectifier coupled with a step down transformer is used for our design. The voltage rating of transformer used is 0-12V and the current rating is 500mA. When AC voltage of 230V is applied across the primary winding an output AC voltage of 12V is obtained. One alteration of input causes the top of transformer to be positive and the bottom negative. The next alteration will temporarily cause the reverse.

Rectifier:-

In the power supply unit, rectification is normally achieved using a solid state diode. Diode has the property that will let the electron flow easily at one direction at proper biasing condition. Bridge rectifiers of 4 diodes are used to achieve full wave rectification. Two diodes will conduct during the negative cycle and the other two will conduct during the positive half cycle.

Filtering unit:-

Filter circuit which is usually a capacitor acts as a surge arrester always follows the rectifier unit. This capacitor is also called as a decoupling capacitor or a bypass capacitor, is used not only to short the ripple with frequency to ground but also leave the frequency of the DC to appear at the output.

Regulators:-

The voltage regulators play an important role in any power supply unit. The primary purpose of a regulator is to aid the rectifier and filter circuit in providing a constant DC voltage to the device. Power supplies without regulators have an inherent problem of changing DC voltage values due to variations in the load or due to fluctuations in the AC line voltage. With a regulator connected to DC output, the voltage can be maintained within a close tolerant region of the desired output. IC 7805 and 7812 regulators are used in this project for providing a DC voltage of +5V and +12V respectively.

Technical Details:-

Transformer: 230/12 volts step down transformer, 1 ampere Diodes: IN 4007

7805: The 7805 supplies 5 volts at 1 amp maximum with an input of 7-25 volts Electrolytic Capacitors: 100pF, 330pF and 100μF, power rating of 25V.

Features:-

· Gives a well regulated +12V and +5V output voltages

· Built in overheating protection shuts down output when regulator IC gets too hot. · Very stable output voltages, reliable operation

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Department of Electronics Engg., P.V.P.I.T., Budhgaon · The circuit has overload and thermal protection.

ADVANTAGES:

 78xx series ICs do not require additional components to provide a constant, regulated source of power, making them easy to use, as well as economical and efficient uses of space. Other voltage regulators may require additional components to set the output voltage level, or to assist in the regulation process. Some other designs (such as a switched-mode power supply) may need substantial engineering expertise to implement.

 78xx series ICs have built-in protection against a circuit drawing too much power. They have protection against overheating and short-circuits, making them quite robust in most applications. In some cases, the current-limiting features of the 78xx devices can provide protection not only for the 78xx itself, but also for other parts of the circuit.

DISADVANTAGES:

 The input voltage must always be higher than the output voltage by some minimum amount (typically 2 volts). This can make these devices unsuitable for powering some devices from certain types of power sources (for example, powering a circuit that requires 5 volts using 6-volt batteries will not work using a 7805).

 As they are based on a linear regulator design, the input current required is always the same as the output current. As the input voltage must always be higher than the output voltage, this means that the total power (voltage multiplied by current) going into the 78xx will be more than the output power provided. The extra input power is dissipated as heat. This means both that for some applications an adequate heatsink must be provided, and also that a (often substantial) portion of the input power is wasted during the process, rendering them less efficient than some other types of power supplies. When the input voltage is significantly higher than the regulated output voltage (for example, powering a 7805 using a 24 volt power source), this inefficiency can be a significant issue.

 Even in larger packages, 78xx integrated circuits cannot supply as much power as many designs which use discrete components, and are generally inappropriate for applications requiring more than a few amperes of current.

 Each specific model of 78xx is designed to produce only one fixed voltage output, so they may not be suitable for applications requiring a configurable or varying output (For such applications, the LM317 series of ICs are available, which are similar to 78xx ICs but can produce a configurable voltage).

± 5V and ±12V regulated power supply using Proteus.

Component:

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1. From main page of Proteus, click on ‗P‘ to click device from library.

2. In pick device, insert the component which has to be selected & click on ‗OK‘. 3. Then place the all components on the Proteus screen.

4. Right click the component properties to change the required value 5. Add voltage probe at input and output of diagram.

6. Select the graph mode & choose AC sweep analysis option

7. Right click in the graph window and select add traces(input & output trace). 8. Right click & activate simulate graph

9. Observe input & output waveforms and analysis the results.

CIRCUIT SIMULATION

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By using ± 5V and ±12V regulated power supply using Proteus; we understand that the voltage regulators play an important role in any power supply unit. The primary

purpose of a regulator is to aid the rectifier and filter circuit in providing a constant DC voltage. To avoid variations in the load or due to fluctuations in the AC

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Padmabhooshan Vasantraodada Patil Institute of Technology,

Budhgaon-416304

Department of Electronics Engineering

Circuit Simulation

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Study and Analysis of Non inverting amplifier.

Aim:

Design, simulate and analyze non inverting amplifier using IC 741 using following tools 1) Analogue analysis 2) Frequency analysis 3) Noise analysis 4) Distortion analysis Objectives:

• To understand principal of working of Non inverting amplifier • To understand the circuit arrangement of Non inverting amplifier

• To understand the simulation procedure of Non inverting amplifier circuit using proteus.

• To observe & analyze the output waveforms using different analysis tools. Outcomes:

• Able to understand principal of working of Non inverting amplifier circuit. • Able to understand the circuit arrangement of Non inverting amplifier circuit. • Able to understand the simulation procedure Non inverting amplifier circuit

using Proteus.

• Able to observe & analyse the circuit.

• To enable student to analyse solve electronics engineering problem by applying basic principles of mathematics , sciences and engineering and also be able to use modern engineering techniques , skills and tools to fulfill social needs • To enable to innovate , design and develop a variety of electronic and computer

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Non-inverting amplifier is one of the most popular op amp circuits similar to Op amp inverting amplifier circuit. It provides a gain to the input signal without any change in the polarity. If a sine wave is fed to the input of this op amp non inverting amplifier, the output

will be an amplified sine wave with zero phase shift.

Here the input is applied to the non inverting terminal of the op amp. The non inverting amplifier gain is given by the expression A=1+R3/R2 where R2 is the feedback resistance and R3 is the input resistance. The input impedance of non-inverting amplifier is extremely large, typically 100MΩ.

Working of Non- inverting Amplifier:-

 The second basic configuration of an operational amplifier circuit is that of a Non-inverting Amplifier. In this configuration, the input voltage signal, (Vin ) is applied directly to the non-inverting ( + ) input terminal which means that the output gain of the amplifier becomes "Positive" in value. The result of this is that the output signal is "in-phase" with the input signal.

 Feedback control of the non-inverting amplifier is achieved by applying a small part of the output voltage signal back to the inverting ( - ) input terminal via a R3- R2 voltage divider network, again producing negative feedback. This closed-loop configuration produces a non-inverting amplifier circuit with very good stability, a very high input impedance, R1 approaching infinity, as no current flows into the positive input terminal, (ideal conditions) and a low output impedance, Rout as shown below.

 The working of non inverting amplifier is similar to that of inverting amplifier except that the output has no phase shift here.

 The resistors R2 and R3 form a voltage divider network.

 A negative feedback is provided by applying a little of output voltage to the inverting input terminal through the potential divider network R2 and R3.

 The voltage gain of the amplifier is determined by the ratios of R3 and R2 since Gain, A=1+R3/R2

So the amplitude of the output voltage signal can be varied by varying either of the resistors R2 or R3

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Department of Electronics Engg., P.V.P.I.T., Budhgaon Theory:-

• Closed loop configuration

1) Non-inverting amplifier 2) Inverting amplifier 3) Differential amplifier 1. Non-inverting amplifier

Non-inverting amplifier is voltage series feedback amplifier. The input signal is given to the non-inverting terminal of op-amp & output signal is in same phase with input. So it is called as non inverting amplifier.

• Closed loop voltage gain

The closed loop voltage gain is given by, Af=Vo/Vin . . . .(1) The output voltage Vo is given by, Vo=A*(Vid)

=A*(V1-V2) . . . (2) where V1=Vin V2=Vf

Therefore feed back voltage Vf is given by, Vf=(R2/R2+Rf)*Vo . . . (3)

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Department of Electronics Engg., P.V.P.I.T., Budhgaon Vo=A*(Vin-R2*Vo/R2+Rf)

Vo(1+AR2/R2+Rf)=AVin Vo/Vin=A/(R2+Rf+AR2/R2+Rf) Af=A(R2+Rf)/(R2+Rf+AR2) . . . . .(4) Generally A is very large.

Therfore AR2>>R2+Rf & R2+Rf+AR2=AR2 Therefore Af=(R2+Rf)/R2

Af=1+Rf/R2 . . . .(5)

The gain of voltage seriers feedback amplifier is determined by the two resistances R2& Rf. • Closed loop voltage gain (Af) in terms of open loop gain(A)

The feedback voltage is given by, Vf=(R2/R2+Rf)*Vo

Vf/Vo=R2/R2+Rf

Vf/Vo=B=R2/R2+Rf . . . .(6)

The closed loop gain (Af) is expressed as follows from Eq (4) Af=A(R2+Rf)/(R2+Rf+AR2) . . . (7)

Rearranging Eq (7),we get, Af=A/(1+AB)

where B=R2/R2+Rf • Input resistance with feedback

Input resistance of op-amp with feedback is the equivalent resistance which observed from the non-inverting input.

Let Rf is the feedback resistance & Ri is the input resistance of op-amp.So the input resistance of op-amp with feedback is given by,

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Department of Electronics Engg., P.V.P.I.T., Budhgaon Rif=Vin/Iin . . . .(8)

where Iin=Vid/Ri

Rif=Vin/(Vid/Ri) . . . .(9) However,

Vid=Vo/A & Vo=(A/1+AB)*Vin . . . .(10)

substitute the Eq (10) in Eq (9), we get, Rif=Vin/(Vo/ARi)

=Ri*Vin/(Vo/A)

=Ri*Vin/((A/1+AB)*(Vin/A)) =Ri*(1+AB) . . . .. . . (11)

So from Eq (11), we conclude that the input resistance of non-inverting amplifier with feedback is (1+AB) times Ri.

• The output resistance (Ro) with feedback

The output resistance (Ro) wiyh feedback is the resistance that is observed backward from the output terminal.

The analysis is done by using thevenin's theorem of circuit. In this the independant source is reduced to zero and apply external voltage Vo and current Iois calculated.

Rof=Vo/Io . . .. . . .(12) By applying kirchoff's current law, Io=Ia+Ib . . . .. . (13) since (Rf+R2)||Ri>>Ro & Ia>>Ib

Therefore by applying kirchoff's voltage law for output loop, vo-RoIo-AVid=0

Io=Vo-AVid/Ro . . . .(14) However, Vid=V1-V2

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Department of Electronics Engg., P.V.P.I.T., Budhgaon therefore Vid=-Vf

=-(R2/R2+Rf)*Vo

=-BVo . . . (15)

substituting the value of Vid in Eq (14), we get, Io=Vo-A(-BVo)/Ro

Io=Vo+ABVo/Ro . . . (16)

substitute the value of Io from Eq (16) in Eq (12), Rof=Vo/(Vo+ABVo/Ro)

=Ro/1+AB . . . (17)

From Eq (17), we can conclude that the output resistance of voltage series feedback amplifier is 1/1+AB times Ro.

Non-inverting amplifier circuit using Proteus

Components Required :

Name Description Number of components

required IC IC 741 1 Multi cell battery Multi cell battery(12V) 2 RES Resistor(10K) 3 PULSE As Input 1 GND Ground 1

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Department of Electronics Engg., P.V.P.I.T., Budhgaon Procedure using Proteus:

Step 1:-Selection of components 1) Selection of OP-AMP:-

 Activate component mode

 Go to pick components (click on ‗P‘)

 Type 741 in search section

 Select IC 741

 Place the component in circuit 2) Selection of Resistors:-

 Again go to pick component section

 And select three generic resistors

 Place these 3 resistors in circuit at required place

 Then go to edit properties by right clicking on that component

 Set each resistor to 10 kilo ohm 3) Selection of batteries:-

 Again go to pick component section

 Then go to Miscellaneous

 And select multi cell batteries

 Place those batteries in circuit

 Choosing edit properties option set batteries to 12V 4) Select sine generator from generator section

5) Do the connections (wiring)as per circuit diagram

6) Add voltage probe at the 6 th and pin of operational amplifier (741) Step 2:-Simulation

Graph Analysis:-

 Go to graphs option and select analogue

 Drag that graph in circuit section

 Insert voltage probe in graph section

 Go to ‗add trace‘ and add the traces of input and output

 Right click and activate simulate graph option

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we have studied operation of non-inverting amplifier. We have observed input and output waveforms for the given gain parameter. Also with the help of analogue, frequency, noise and distortion options and different graphs we have analysed the noninverting amplifier.

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Padmabhooshan Vasantraodada Patil Institute of Technology,

Budhgaon-416304

Department of Electronics Engineering

Circuit Simulation

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Design a simple circuit using RLC Component to observe transient response using

Proteus.

Objectives:

• To understand principal of working of Transient Response of RLC Circuit • To understand the circuit arrangement of Transient Response of RLC Circuit • To understand the procedure of Transient Response of RLC Circuit circuit

using proteus.

• To observe the simulation of circuit

Outcomes:

• Able to study Transient Response of RLC Circuit.

• Able to understand the circuit arrangement of Transient Response of RLC Circuit.

• Able to understand the procedure of Transient Response of RLC Circuit in proteus.

• Able to observe the simulation of circuit.

• To enable student to analyse solve electronics engineering problem by applying basic principles of mathematics , sciences and engineering and also be able to use modern engineering techniques , skills and tools to fulfill social needs

• To enable to innovate ,design and develop a variety of electronic and computer based components and system for applications including signal processing , communication , computer network and control system.

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Department of Electronics Engg., P.V.P.I.T., Budhgaon Introduction-

An RLC circuit (or LCR circuit or CRL circuit or RCL circuit) is an electrical circuit consisting of a resistor, an inductor, and a capacitor, connected in series or in parallel. The RLC part of the name is due to those letters being the usual electrical symbols for resistance, inductance and capacitance respectively. The circuit forms a harmonic oscillator for current and will resonate in a similar way as an LC circuit will. The main difference that the presence of the resistor makes is that any oscillation induced in the circuit will die away over time if it is not kept going by a source. This effect of the resistor is called damping. The presence of the resistance also reduces the peak resonant frequency somewhat. Some resistance is unavoidable in real circuits, even if a resistor is not specifically included as a component. A pure LC circuit is an ideal which really only exists in theory.

There are many applications for this circuit. They are used in many different types of oscillator circuits. Another important application is for tuning, such as in radio receivers or television sets, where they are used to select a narrow range of frequencies from the ambient radio waves. In this role the circuit is often referred to as a tuned circuit. An RLC circuit can be used as a band-pass filter, band-stop filter, low-pass filter or high-pass filter. The tuning application, for instance, is an example of band-pass filtering. The RLC filter is described as a second-order circuit, meaning that any voltage or current in the circuit can be described by a second-order differential equation in circuit analysis

Circuit diagram –

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Inductor and Capacitor connected in series or in parallel. Output is taken across the capacitor of 10uF.

Theory:

Transient response-

a transient response or natural response is the response of a system to a change from equilibrium. The transient response is not necessarily tied to "on/off" events but to any event that affects the equilibrium of the system. The impulse response and step response are transient responses to a specific input (an impulse and a step, respectively

Plot showing underdamped and overdamped responses of a series RLC circuit. The critical damping plot is the bold red curve. The plots are normalised for L=1, C=1 and

The differential equation for the circuit solves in three different ways depending on the value of . These are underdamped ( ), overdamped ( ) and critically damped ( ). The differential equation has the characteristic equation.

The roots of the equation in s are,[6]

The general solution of the differential equation is an exponential in either root or a linear superposition of both,

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The coefficients A1 and A2 are determined by the boundary conditions of the specific problem

being analysed. That is, they are set by the values of the currents and voltages in the circuit at the onset of the transient and the presumed value they will settle to after infinite time.[7]

Properties-

Typical second order transient system properties Rise time

Rise time refers to the time required for a signal to change from a specified low value to a specified high value. Typically, these values are 10% and 90% of the step height. Overshoot

Overshoot is when a signal or function exceeds its target. It is often associated with ringing.

Settling time

Settling time is the time elapsed from the application of an ideal instantaneous step input to the time at which the output has entered and remained within a specified error band.

Delay time

The delay time is the time required for the response to reach half the final value the very first time.

Peak time

The peak time is the time required for the response to reach the first peak of the overshoot.

RLC circuit using Proteus

Components required:

Name Description Number of components

required

RES Resistor 1

CAP Capacitor 1

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GND Ground 1

Procedure using Proteus:

6. Select the ‗graph mode‘ & choose analouge Analysis graph window. 7. Right click and select ‗add traces‘ (input & output trace).

9. Observe and analysis input & output waveforms.

Circuit Stimulation Using Proteus

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We understand the transient response using RLC circuit in proteus software. We observe the simulation of circuit & study the transient response.

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Padmabhooshan Vasantraodada Patil Institute of Technology,

Budhgaon-416304

Department of Electronics Engineering

Circuit Simulation

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Simulation of Astable Multivibrator using transistor using Proteus.

Aim:

Design & simulate the Astable Multivibrator using transistor.

Objectives:

• To understand principal of working of Astable Multivibrator. • To understand the circuit arrangement of Astable

Multivibrator

• To understand the procedure of Astable Multivibrator using transistor circuit using proteus.

• To observe the waveforms and analyze the circuit

Outcomes:

• Able to study Astable Multivibrator using transistor.

• Able to understand the circuit arrangement of Astable Multivibrator

• Able to understand the procedure of Astable Multivibrator using transistor circuit using proteus.

• Able to observe the simulation and analysis of circuit.

• To enable student to analyse solve electronics engineering problem by applying basic principles of mathematics , sciences and engineering and also be able to use modern engineering techniques , skills and tools to fulfill social needs

• To enable to innovate , design and develop a variety of electronic and computer based components and system for applications including signal processing , communication , computer network and control system.

Introduction:

An astable multivibrator is a regenerative circuit consisting of two amplifying

stages connected in a positive feedback loop by two capacitive-resistive coupling networks. The amplifying elements may be junction or field-effect transistors, vacuum tubes,operational amplifier or other types of amplifier. The example diagram shows bipolar junction transistors.

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one will have high voltage while the other has low voltage, (except during the brief transitions from one state to the other)

Circuit Diagram:

Theory: Operation:

The circuit has two stable states that change alternatively with maximum transition rate because of the "accelerating" positive feedback. It is implemented by the coupling capacitors that instantly transfer voltage changes because the voltage across a capacitor cannot suddenly change. In each state, one transistor is switched on and the other is switched off. Accordingly, one fully charged capacitor discharges (reverse charges) slowly thus converting the time into an exponentially changing voltage. At the same time, the other empty capacitor quickly charges thus restoring its charge (the first capacitor acts as a time-setting capacitor and the second prepares to play this role in the next state). The circuit operation is based on the fact that the forward-biased base-emitter junction of the switched-on bipolar transistor can provide a path for the capacitor restoratiswitched-on

State 1 (Q1 is switched on, Q2 is switched off):

In the beginning, the capacitor C1 is fully charged (in the previous State 2) to the power supply voltage V with the polarity shown in Figure 1. Q1 is on and connects the left-hand positive plate of C1 to ground. As its right-left-hand negative plate is connected to Q2 base, a maximum negative voltage (-V) is applied to Q2 base that keeps Q2 firmly off. C1 begins discharging (reverse charging) via the high-value base resistor R2, so that the voltage of its

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right-hand plate (and at the base of Q2) is rising from below ground (-V) toward +V. As Q2 base-emitter junction is backward-biased, it does not conduct, so all the current from R2 goes into C1. Simultaneously, C2 that is fully discharged and even slightly charged to 0.6 V (in the previous State 2) quickly charges via the low-value collector resistor R4 and Q1 forward-biased base-emitter junction (because R4 is less than R2, C2 charges faster than C1). Thus C2 restores its charge and prepares for the next State 2 when it will act as a time-setting capacitor. Q1 is firmly saturated in the beginning by the "forcing" C2 charging current added to R3 current; in the end, only R3 provides the needed input base current. The resistance R3 is chosen small enough to keep Q1 (not deeply) saturated after C2 is fully charged.

When the voltage of C1 right-hand plate (Q2 base voltage) becomes positive and reaches 0.6 V, Q2 base-emitter junction begins diverting a part of R2 charging current. Q2 begins conducting and this starts the avalanche-like positive feedback process as follows. Q2 collector voltage begins falling; this change transfers through the fully charged C2 to Q1 base and Q1 begins cutting off. Its collector voltage begins rising; this change transfers back through the almost empty C1 to Q2 base and makes Q2 conduct more thus sustaining the initial input impact on Q2 base. Thus the initial input change circulates along the feedback loop and grows in an avalanche-like manner until finally Q1 switches off and Q2 switches on. The forward-biased Q2 base-emitter junction fixes the voltage of C1 right-hand plate at 0.6 V and does not allow it to continue rising toward +V.

State 2 (Q1 is switched off, Q2 is switched on):

Now, the capacitor C2 is fully charged (in the previous State 1) to the power supply voltage V with the polarity shown in Figure 1. Q2 is on and connects the right-hand positive plate of C2 to ground. As its left-hand negative plate is connected to Q1 base, a maximum negative voltage (-V) is applied to Q1 base that keeps Q1 firmly off. C2 begins discharging (reverse charging) via the high-value base resistor R3, so that the voltage of its left-hand plate (and at the base of Q1) is rising from below ground (-V) toward +V. Simultaneously, C1 that is fully discharged and even slightly charged to 0.6 V (in the previous State 1) quickly charges via the low-value collector resistor R1 and Q2 forward-biased base-emitter junction (because R1 is less than R3, C1 charges faster than C2). Thus C1 restores its charge and prepares for the next State 1 when it will act again as a time-setting capacitor...and so on... (the next explanations are a mirror copy of the second part of Step 1).

Output pulse shape

The output voltage has a shape that approximates a square waveform. It is considered below for the transistor Q1.

During State 1, Q2 base-emitter junction is backward-biased and the capacitor C1 is "unhooked" from ground. The output voltage of the switched-on transistor Q1 changes rapidly from high to low since this low-resistive output is loaded by a high impedance load (the series connected capacitor C1 and the high-resistive base resistor R2).

During State 2, Q2 base-emitter junction is forward-biased and the capacitor C1 is "hooked" to ground. The output voltage of the switched-off transistor Q1 changes exponentially from

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To approach the needed square waveform, the collector resistors have to be low resistance. The base resistors have to be low enough to make the transistors saturate in the end of the restoration (RB < β.RC).

Astable Multivibrator using transistor circuit using proteus.

Component:

Name Description Number of

components required RES Resistor 4 CAP Capacitor 2 VDC Dc voltage source 1 TRANS. Transistor 2 GND Ground 1

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Department of Electronics Engg., P.V.P.I.T., Budhgaon Procedure using Proteus:

1. From main page of Proteus, click on ‗P‘ to click device from library.

2. In pick device, insert the component which has to be selected & click on ‗OK‘. 3. Then place the all components on the Proteus screen.

4. Right clik the component properties to change the required value 5. Add voltage probe at input and output of diagram.

6. Select the graph mode & choose AC sweep analysis option

7. Right click in the graph window and elect add traces(input & output trace). 8. Right click & activate simulate graph

9. Observe input & output waveforms and analysis the results.

CIRCUIT SIMULATION USING PROTES

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can observe the simulation of circuit & analyse the waveforms taken across capacitor C2. Astable multivibrator has no stable state. It generates square wave of predetermined frequency. Hence it is a square wave generator.

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Padmabhooshan Vasantraodada Patil Institute of Technology,

Budhgaon-416304

Department of Electronics Engineering

Circuit Simulation

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Design & stimulate the Astable Multivibrator using 555.

Objectives:

 To understand principal of working of Astable Multivibrator.

 To understand the circuit arrangement of Astable Multivibrator

 To study Astable Multivibrator using IC 555.

 To understand the procedure of ―Astable Multivibrator using IC 555‖ circuit using proteus.

 To observe the simulation of circuit.

Outcomes:

 Able to study Astable Multivibrator using IC 555.

 Able to understand the circuit arrangement of Astable Multivibrator

 Able to understand the procedure of ―Astable Multivibrator using IC 555‖ circuit using proteus.

 Able to observe the simulation of circuit.

 To enable student to analyse solve electronics engineering problem by applying basic principles of mathematics , sciences and engineering and also be able to use modern engineering techniques , skills and tools to fulfill social needs

 To enable to innovate , design and develop a variety of electronic and computer based components and system for applications including signal processing , communication , computer network and control system.