LABORATORY MANUAL

ECE -208

UNIFIED ELECTRONICS LABORATORY-II

COURSE CONTENTS

S.No. Description

1. Simulation using p-spice for zener diode used a a voltage regulator.

2. Simulation using p-spice for operational amplifier as summer.

3. Simulation of network theorem using p-spice.

4. Design and analyse a differentiator circuit whose minimum frequency is 100KHz

5. Design and analyse a integrator circuit whose maximum frequency is 100KHz.

6. To analyze the characteristics of instrumentation amplifier using bread board and PSpice.

7. To analyze the functionality of triangular wave generator using IC -741

8. To determine frequency response of cascade amplifier Darlington pair.

9.

To determine the frequency response of two stage RC coupled amplifier using complementary symmetry push-pull amplifier

10. To analyze the functionality of Colpitt oscillator on output frequency using bread board and PSPICE

11.

Implement phase shift oscillator using bread board and Pspice.

12.To analyze the functionality of Hartley oscillator on output frequency using bread board and PSPICE

EXPERIMENT 1

Title:- Simulation using P-Spice for Zener diode used as voltage regulator. Software Used- P-Spice

Learning Objective: Through this experiment the working of zener diode will be proved.

Procedure: The circuit of fig. 1 will be drawn on schematic editor of the software.

1. Use the circuit elements from the components option in P-Spice software. 2. For making the connections between components use the wire option from

the tool bar. 3. Use the power supply from the power supply option. 4. Use the zener diode from circuit components.

Observation:

Sr. No. Input Voltage Resistance Output Voltage

Result: The voltage across the resistance R2 will be kept constant at the voltage of 5V through the use of zener diode.

Cautions: 1. All connection between the circuit elements must be proper.

EXPERIMENT 2

Title- Simulation using PSpice for operational amplifier used as summer. Software Used:- PSpice Software

Learning Objective: - How a operational amplifier can be used as a summer of different signals.

Procedure: 1. Use the IC-741 . Pin number 3 is grounded .2. Pin number 3 of IC-741 is connected through three voltage sources

through three resistances.3. For making connection use the wire on the tool bar. 4. Connect a resistance of value R between pin 2 and pin 6. 5. Connect the CRO at the output pin 6 of IC-741 to see the result.

Circuit Diagram:

Draw the above circuit in schematic and run the program.

Results: The result of the above experiment will be the summation of the three input voltages.

Vout = - (V1+V2+V3)

Cautions :1) Make proper connections between all the circuit elements.

EXPERIMENT 3

Title- Simulation of network theorems using PSpiceSoftware Used:- PSpice Software

Learning Objective: - Learning of superposition theorem through the use of PSpice software

Procedure:

1)For getting the voltage across the R2 first we will find the voltage across the R2 due to only supply voltage B1 . for this the circuit of fig.2 will be drawn.In this circuit except the B1 supply voltage all other supply voltage will be short circuited.

2)Then find the voltage across R2 due to only the B2 supply and draw the circuit of fig.3 .In this circuit all supply voltages except the B2 will be short circuited.

3)After finding the separate voltages due to supply voltage B1 and B2 we will use the superposition theorem and add the two voltages. That will be the final voltage across the R2.

Fig.2

Fig. 3

Observation:-

Sr. No. Resistance Resistance Resistance Voltage Voltage TotalR1 R2 R3 due to B1 due to B2 voltage

The result: - The resulting voltage across R2 will be the total summation of the voltages due to B1 and B2.

Cautions:1. All connection must be proper.

EXPERIMENT 4

Title: Design and analyse a differentiator circuit whose minimum frequency is 100Hz.

APPARATUS REQUIRED:

S.No. Apparatus Specification Quantity Tolerence1 Operational 01

amplifierLM348

2 Resistor 1KΩ, 2KΩ 02 5%3 Capacitor 0.01µF 034 Bread Board 015 Power Supply 016 Connecting As per

wires requirement

CIRCUIT DIAGRAM:

Rin= 1KΩ, RF= 2KΩ

Procedure

1. Using power supply voltages of ±15 VDC for the op-amp, construct an inverting amplifier circuit with a gain of -3.9 using an input resistor of 1 K Ohms. Install the 0.01 µF capacitor in parallel with the feedback resistor as seen in Fig. 1. Calculate the cutoff frequency (fc) for the circuit using the measured values of the components. It should be around 400 Hz. Add two extra 0.1 µF capacitors to the circuit. One should be connected between the + DC supply(pin 4) and ground the other should be connected between the - DC supply(pin 11) and ground. These capacitors are to help prevent oscillation in the amplifier circuit due to interaction between the circuit and the power supply. They should be placed as close to the Op-Amp itself as physically possible. Make sure that the circuit is correctly connected before turning on the power supply voltages. Failure to do so may cause the op-amp to saturate and in some cases cause permanent damage to the op-amp.

2. Set the signal input, vin, to zero. That is replace the signal source, vin, with a short circuit to ground. Carefully measure the DC output voltage. Make sure you record the proper sign, It should be between +50 mV and -50 mV, usually very small. This output with no input is called the output offset voltage. It is an error in the output of the circuit. It can be treated as an equivalent input offset voltage applied to the non-inverting input of the op-amp. The equivalent input offset is calculated by dividing the measured output offset by the gain of the amplifier from the non-inverting input, Av = (1 + Rf /Rin). This offset has no effect on the ac operation of the circuit, but can cause errors in dc measurements of small voltages.

3. Use a signal input voltage, vin, of 0.1 VDC and connect it to the amplifier signal input as Vin. Using a digital Multi-meter, measure and record both Vin and Vout as accurately as possible. Calculate the DC voltage gain both with and without correcting the output voltage by subtracting the output offset voltage measured in step 2 from the measured output voltage. Be sure to use the correct sign on the offset voltage. Repeat this measurement and calculation with Vin = 1.0 VDC.

4. With an oscilloscope connected to both the signal input and the output, apply an A.C. signal such that the output voltage has amplitude between 5V and 10V. Then measure Vin, Vout, T, and t(for phase measurement) at your calculated cutoff frequency and at each of the following frequencies: 20Hz, 50Hz, 100Hz, 200Hz, 500Hz, 1kHz, 2kHz, 5kHz and 10kHz, 20kHz, 50kHz. Print a copy of the waveforms at 20 Hz and 10 kHz, and at your calculated cutoff frequency. As the gain starts to drop increase the input voltage trying to keep the output voltage amplitude between 5V and 10V until you reach the maximum output of the signal generator. Also take these measurements at your calculated cutoff frequency. If the output waveform starts to look like a triangular wave instead of a sine wave your amplifier has reached the slew rate limit and you will have to reduce the input voltage until this effect is eliminated to get accurate gain measurements

5. Calculate the AC voltage gain and phase shift of the circuit at each frequency.

6. Set your signal generator to square wave output at 100 Hz with amplitude of 1 V. With this input observe and record the output waveform. Repeat at a frequency of 500 Hz.

CALCULATIONS / GRAPHS :

Gain(dB) = 20 log (Vo/Vi)

OBSERVATION TABLE

S.No. Frequency(Hz) Vi(V) Vo(V) Gain(dB)

1(1k 0r 2k) 500 6*.5=3v 2*.5=1v

2(1k or 2k) 1000 7*.5=3.5 3*.5=1.5v

3(1k or 2k) 1500 8*.5=4 4*.5=2v

OBSERVATION TABLE CONSIDERING ERRORS DUE TO MEASURING EQUIPMENTS: (CRO)

S.No Freq.(Hz Freq.(Hz Vo( Vo( Vi(V Gain(dB)m Gain(dB)m. )+2% ) -2% V) V) - ) in ax

+2% 2%

Calculations considering component errors:

2)Calculate RFmax=RF±10%, R1min= R1±10%.

3)Calculate Vo min and Vo max

Vo min = - (RFmin / R1min)Vi min

Vo max = (1+ RFmax / R1max) V i max

4)Find theoretical avg. gain and practical average gain.

5)Then find %age error = (theoretical gain – practical gain)/theoretical gain.

Plot the graph between

1)Min. frequency and min gain 2)Min. frequency and max. gain 3)Max. frequency and min. gain 4)Max. frequency and max. gain

Conclusion:-Drawn from the results of the experiment.

Cautions:1. All connection must be proper. 2. All connections must be tight. 3. Use the correct IC.

EXPERIMENT NO – 5

Title: Design and analyse a integrator circuit whose maximum frequency is 100KHz.

APPARATUS REQUIRED:

S.No. Apparatus Specification Quantity Tolerence1 Operational 01

amplifierLM348

2 Resistor 1KΩ, 2KΩ 02 5%3 Capacitor 0.1µF 034 Bread Board 015 Power Supply 016 Connecting As per

wires requirement

CIRCUIT DIAGRAM:

Rin= 1KΩ, RF= 2KΩ

Procedure

1. Using power supply voltages of ±15 VDC for the op-amp, construct an inverting amplifier circuit with a gain of -3.9 using an input resistor of 1 K Ohms. Install the 0.1 µF capacitor in parallel with the feedback resistor as seen in Fig. 1. Calculate the cutoff frequency (fc) for the circuit using the measured values of the components. It should be around 400 Hz. Add two extra 0.1 µF capacitors to the circuit. One should be connected between the + DC supply(pin 4) and ground the other should be connected between the - DC supply(pin 11) and ground. These capacitors are to help prevent oscillation in the amplifier circuit due to interaction between the circuit and the power supply. They should be placed as close to the Op-Amp itself as physically possible. Make sure that the circuit is correctly

connected before turning on the power supply voltages. Failure to do so may cause the op-amp to saturate and in some cases cause permanent damage to the op-amp.

2. Set the signal input, vin, to zero. That is replace the signal source, vin, with a short circuit to ground. Carefully measure the DC output voltage. Make sure you record the proper sign, It should be between +50 mV and -50 mV, usually very small. This output with no input is called the output offset voltage. It is an error in the output of the circuit. It can be treated as an equivalent input offset voltage applied to the non-inverting input of the op-amp. The equivalent input offset is calculated by dividing the measured output offset by the gain of the amplifier from the non-inverting input, Av = (1 + Rf /Rin). This offset has no effect on the ac operation of the circuit, but can cause errors in dc measurements of small voltages.

3. Use a signal input voltage, vin, of 0.1 VDC and connect it to the amplifier signal input as Vin. Using a digital Multi-meter, measure and record both Vin and Vout as accurately as possible. Calculate the DC voltage gain both with and without correcting the output voltage by subtracting the output offset voltage measured in step 2 from the measured output voltage. Be sure to use the correct sign on the offset voltage. Repeat this measurement and calculation with Vin = 1.0 VDC.

4. With an oscilloscope connected to both the signal input and the output, apply an A.C. signal such that the output voltage has amplitude between 5V and 10V. Then measure Vin, Vout, T, and t(for phase measurement) at your calculated cutoff frequency and at each of the following frequencies: 20Hz, 50Hz, 100Hz, 200Hz, 500Hz, 1kHz, 2kHz, 5kHz and 10kHz, 20kHz, 50kHz. Print a copy of the waveforms at 20 Hz and 10 kHz, and at your calculated cutoff frequency. As the gain starts to drop increase the input voltage trying to keep the output voltage amplitude between 5V and 10V until you reach the maximum output of the signal generator. Also take these measurements at your calculated cutoff frequency. If the output waveform starts to look like a triangular wave instead of a sine wave your amplifier has reached the slew rate limit and you will have to reduce the input voltage until this effect is eliminated to get accurate gain measurements

5. Calculate the AC voltage gain and phase shift of the circuit at each frequency.

6. Set your signal generator to square wave output at 100 Hz with amplitude of 1 V. With this input observe and record the output waveform. Repeat at a frequency of 500 Hz.

CALCULATIONS / GRAPHS :

Gain(dB) = 20 log (Vo/Vi)

OBSERVATION TABLE

S.No. Frequency(Hz) Vi(V) Vo(V) Gain(dB)

OBSERVATION TABLE CONSIDERING ERRORS DUE TO MEASURING EQUIPMENTS: (CRO)

S.No Freq.(Hz Freq.(Hz Vo( Vo( Vi(V Gain(dB)m Gain(dB)m. )+2% ) -2% V) V) - ) in ax

+2% 2%

Calculations considering component errors:

6)Calculate RFmax=RF±10%, R1min= R1±10%.

7)Calculate Vo min and Vo max

Vo min = - (RFmin / R1min)Vi min

Vo max = (1+ RFmax / R1max) V i max

8)Find theoretical avg. gain and practical average gain.

9)Then find %age error = (theoretical gain – practical gain)/theoretical gain.

Plot the graph between

5)Min. frequency and min gain 6)Min. frequency and max. gain 7)Max. frequency and min. gain 8)Max. frequency and max. gain

Conclusion:-Drawn from the results of the experiment.

Cautions:1. All connection must be proper. 2. All connections must be tight. 3. Use the correct IC.

Experiment 6

Title: To analyze the characteristics of instrumentation amplifier using bread board and PSpice..

APPARATUS REQUIRED:

S.No. Apparatus Specification Quantity Tolerence1 Op amps 741 032 Resistor 1KΩ, 2KΩ 08 5%3 Bread Board 014 Power Supply 015 Connecting wires As per

requirement

Theory:

An instrumentation (or instrumentational) amplifier is a type of differential amplifier that has been outfitted with input buffers, which eliminate the need for input impedance matching and thus make the amplifier particularly suitable for use in measurement and test equipment. Additional characteristics include very low DC offset, low drift, low noise, very high open-loop gain, very high common-mode rejection ratio, and very high input impedances. Instrumentation amplifiers are used where great accuracy and stability of the circuit both short- and long-term are required.

Circuit Diagram

Frequency Input voltage Input Ooutput 20log(vo/vi )1 K Hz (v1) voltage voltage

(v2 ) Vo

EXPERIMENT 7

Title- To analyse the functionality of triangular wave generator using IC 741

Equipments Used :

S.No. Apparatus Specification Quantity Tolerence1 Operational 02

amplifierLM348

2 Resistor 1KΩ, 2KΩ 03 5%3 Capacitor 0.1µF 014 Bread Board 015 Power Supply 016 Connecting As per

wires requirement

Circuit Diagram:

Procedure: 1) connect the pin 2 of the operational amplifier IC 741 (i) with a resistance r1 and pin 6 of the operational amplifier IC 2nd .2) Connect a capacitor C1 between pin 2 and pin 6 of the op-amp IC 1st. 3) Connect the pin 6 of op-amp 1st to the oin 2 of op-amp 2nd through a resistance R2. 4) Connect a resistance R3 between pin 2 of op-amp 1st and pin 6 of op-amp 2nd. 5) Connect the pin 3 of op-amp IC 1st to ground. 6) Connect the pin 3 of op-amp IC 2nd to ground. 7) The output pin 6 of op-amp 1st will generate the triangular wave.

Observation:

Sr. No. R1 C1 Time Constant

Result: - The output of the first op-amp will be triangular wave .

Precautions:4. All connections must be correct. 5. Use correct IC .

Experiment 8

Title: To determine the frequency response of cascade amplifier Darlington pair using bread board and PSPICE

APPARATUS REQUIRED:

S.No. Apparatus Specification Quantity Tolerence1 Transistor 042 Resistor Ckt Reqt 5%3 Capacitor 40µF 024 Bread Board 015 Power Supply 20V 016 Connecting wires

Theory:

In electronics, the Darlington transistor (often called a Darlington pair) is a compound structure consisting

of two bipolar transistors (either integrated or separated devices) connected in such a way that the current

amplified by the first transistor is amplified further by the second one. This configuration gives a much

higher current gain than each transistor taken separately and, in the case of integrated devices, can take

less space than two individual transistors because they can use a shared collector. Integrated Darlington

pairs come packaged singly in transistor-like packages or as an array of devices (usually eight) in

an integrated circuit.

Circuit Diagram:

OBSERVATION TABLE

Frequency Output voltage Input voltage Gain 20log(vo/vi )(f) kHz (vo) (vi ) (vo/vi )

Result and Conclusion:-Draw the frequency response.

EXPERIMENT NO. 9

Title: To determine the frequency response of two stage RC coupled amplifier using complementary symmetry push pull amplifier

APPARATUS REQUIRED:

S.No. Apparatus Specification Quantity Tolerance1 Transistor 052 Diodes 023 Resistor 1KΩ, 2KΩ 08 5%4 Capacitor 0.1µF 02

5 Bread Board 016 Power Supply 017 Connecting wires As per

requirement

Circuit Diagram:

OBSERVATION TABLE

Frequency Output voltage Input voltage Gain 20log(vo/vi )(f) (vo) (vi ) (vo/vi )

Result and Conclusion:-Draw the frequency response.

The expected frequency response will be

Cautions:1. All connection must be proper. 2. All connections must be tight. 3. Use the correct IC.

Experiment 10

Title: To implement phase shift oscillator using bread board and PSPICE

APPARATUS REQUIRED:

S.No. Apparatus Specification Quantity Tolerence1 Transistor 012 Resistor 1KΩ, 2KΩ 07 5%3 Capacitor 0.1µF 04

4 Bread Board 015 Power Supply 016 Connecting wires As per

requirement

Theory:

A phase-shift oscillator is a simple electronic oscillator. It contains an inverting amplifier, and a feedback filter which 'shifts' the phase of the amplifier output by 180 degrees at a specific oscillation frequency.The filter produces a phase shift that increases with frequency. It must have a maximum phase shift of considerably greater than 180° at high frequencies, so that the phase shift at the desired oscillation frequency is 180°.The most common way of achieving this kind of filter is using three identical cascaded resistor-capacitor filters, which together produce a phase shift of zero at low frequencies, and 270 degrees at high frequencies. At the oscillation frequency each filter produces a phase shift of 60 degrees and the whole filter circuit produces a phase shift of 180 degrees.

Circuit Diagram:

OBSERVATION TABLE

Change the value Value of C is Frequency Frequency % error inof R constant Calculated Observed frequenfy

Change the value Value of R is Frequency Frequency % error inof C constant Calculated Observed frequenfy

Experiment 11

Title: To analyze the functionality of Hartley oscillator on output frequency using bread board and PSPICEAPPARATUS REQUIRED:

S.No. Apparatus Specification Quantity Tolerence1 Transistor 012 Inductance 023 Resistor 1KΩ, 2KΩ 03 5%4 Capacitor 0.1µF 04

5 Bread Board 016 Power Supply 017 Connecting wires As per

requirement

Theory:

The Hartley oscillator is an electronic oscillator circuit that uses an inductor and a capacitor in parallel to determine the frequency. Invented in 1915 by American engineer Ralph Hartley, the distinguishing feature of the Hartley circuit is that the feedback needed for oscillation is taken from a tap on the coil, or the junction of two coils in series. A Hartley oscillator is essentially any configuration that uses two series-connected coils and a single capacitor. Although there is no requirement for there to be mutual coupling between the two coil segments

Circuit Diagram:

OBSERVATION TABLE

Change the value Value of L2 is Frequency Frequency % error inof L1 constant Calculated Observed frequenfy

Change the value Value of L1 is Frequency Frequency % error inof L2 constant Calculated Observed frequenfy

Experiment 12

Title: To analyze the functionality of Colpitt oscillator on output frequency using bread board and PSPICE

APPARATUS REQUIRED:

S.No. Apparatus Specification Quantity Tolerence1 Transistor 052 Diodes 023 Resistor 1KΩ, 2KΩ 08 5%4 Capacitor 0.1µF 02

5 Bread Board 016 Power Supply 017 Connecting wires As per

requirement

Theory:

A Colpitts oscillator, invented in 1920 by American engineer Edwin H. Colpitts, is one of a number of

designs for electronic oscillator circuits using the combination of an inductance (L) with a capacitor (C) for

frequency determination, thus also called LC oscillator. The distinguishing feature of the Colpitts circuit is

that the feedback signal is taken from a voltage divider made by two capacitors in series. One of the

advantages of this circuit is its simplicity; it needs only a single inductor.

Circuit Diagram

OBSERVATION TABLE

Change the value Value of C2 is Frequency Frequency % error inof C1 constant Calculated Observed frequenfy

Change the value Value of C1 is Frequency Frequency % error inof C2 constant Calculated Observed frequenfy