Dept.

of Electrical and Electronics

Gogte Institute of Technology, Belagavi

Linear IC’s and applications laboratory (18EEL46)

Staff Members

Mr. Balwant K. Patil

Mr. Rahul Suryavanshi

 Experiment No. 1

Design and Implementation of Capacitor Coupled Non-inverting Amplifier and

Inverting Amplifier using single polarity supply.

Objective: To design and demonstrate the single polarity supply Noninverting and
Inverting Amplifier using 741 OPAMP.

Apparatus Required:

Sl. No. Apparatus/ Devices Rating/Quantity

1 OPAMP 741 IC 01
2 Power Supply 24 V (1)
3 Resistors 220kΩ (2),10kΩ, 1kΩ,
4 Capacitors 0.2µF, 2.2 µF, 3.9 µF, 8 µF / 1 each
5 CRO 1
6 BNC connectors 2
7 Patch chords 20

Theory: Presence of coupling capacitors allows the use of single polarity supply for
amplifier applications. Double the value of mentioned supply voltage is to be arranged,
i.e. if double polarity supply mentioned is ±12V, then +24V is to be used for single
polarity application. The voltage divider using resistors R1 & R2 to set biasing voltage of
Vcc/2 at non-inverting terminal is to be done.

For Non-inverting Amplifier R3 & R4 participate in deciding AC gain. R1 & R2 does

biasing; C1 & C2 are coupling capacitors. The roll of C3 is significant as it does not allow
output to saturate, making a circuit to function as follower for input DC signal. There is
no need of an extra capacitor in single polarity inverting amplifier as coupling capacitor
takes care of this issue.
Circuit Diagram:

Fig. No. 1: Non-inverting amplifier (single polarity)

Design:

1. Single polarity Non-inverting Amplifier

I1=100* IB(max)=

R1=R2= VCC/2/I=

R1=R2=

I2 = let Vmin=50mV

R4=Vmin/I2=

g=11 R3+R4/ R4=

C1=1/2*π*fi*( R1||R2)/10= [XC1= (R1||R2)/10]

C2=1/2* π *fi*( RL)/10= [RL=5.6KΩ f1=75Hz]

C3=1/2* π *f1* R4=

Circuit Diagram (Inverting Amplifier Single polarity)

Fig. 2: Inverting Amplifier (Single Polarity supply)

Design

Let VCC= 24V

R1=R2=220K

g=10  VR4 = Vin =IR4 (Assume Vin=50mV)

R4 = g=10  R3=10kΩ

X4= R4/10= at f1 (assume 100Hz/200Hz)

if RL= XC2= RL at f1

C2=
 Procedure:

1. Check the components and patch cords.

2. Connections are made as per the circuit diagram.
3. Set the DC power supply to 24V.
4. Apply an input signal (Sinusoidal) of specified value say 1volt (p-p) at 1 kHz.
5. Observe the input / Output waveforms on CRO and determine gain.

Results/Waveforms:

Student Name USN Date Staff Signature

 Experiment No.2

Design and Implementation of Precision Half/Full Wave Rectifier using 741

OPAMP

Objective: To design precision half wave and full wave rectifier using 741 OPAMP and
observe the performance.

Apparatus Required:

Sl. No. Apparatus/ Devices Rating/Quantity

1 OPAMP 741 IC 01
2 Power Supply +15V and -15V
3 Resistors 3.9k, 820Ω, 1k/1.2k (2), 1.8k (3), 3.6k
4 Diodes 02
5 Signal Generator 01
6 CRO 01
7 BNC connectors 02
8 Patch chords 20

Theory: The circuit of an op-amp precision half wave rectifier is analogous to inverting
amplifier with a diode inserted between the op-amp output terminal and the circuit
output point. When the input signal is negative, the diode is forward biased and the
output observes positive going cycle w.r.t input. Another diode between OPAMP o/p
terminal and inverting input terminal is used to ensure negative feedback for positive
input, not allowing OPAMP o/p to saturate. Precision rectifier circuits compensate the
forward voltage drop of diode. Amplification factor can be changed as per requirement,
and low output impedance.
The output of precision half wave rectifier can be applied to another terminal of
summing amplifier to form Full wave rectifier. The precision full wave rectifier using
noninverting amplifier configuration is demonstrated in circuit no. 2. The circuit can be
analysed using superposition theorem, the top portion of circuit is visualized as
noninverting amplifier from input side and inverting amplifier from node point ‘A’ on
o/p branch.
Circuit Diagram:

Fig. No. 1: Precision Half wave rectifier

Design:

Precision Half Wave Rectifier

I=500µA (Minimum forward current for diodes)

R1=V1/ I1=0.5/500=1KΩ

R2=VO/ I1=2/500=4KΩ [std value 3.9KΩ]

R3=R1|| R2= 1K || 3.9KΩ

=820Ω
 Circuit Diagram

Fig. 02: Precision Full Wave Rectifier

Design:

I=500µA

R6=Vi/ I1=1/500=2KΩ [std value 1.8kΩ]

R4=R5= R6=1.8kΩ

R3=2*R4=3.6kΩ

R1=R3|| R4= 1.2kΩ

R2=R6|| R5= 1kΩ

 Procedure

1. Check the components and patch cords.

2. Connections are made as per the circuit diagram.
3. Set the DC power supply of ±15V.
4. Apply an input signal (Sinusoidal) of specified value say 1volt (p-p) at 1 kHz.
5. Observe the input / Output waveforms on CRO.

Results/Waveforms:

Student Name USN Date Staff Signature

 Experiment No.3

Design and Implementation of Precision Clipper and Clamper using 741 OPAMP

Objective: To design and demonstrate precision clipper and clamper using 741 OPAMP
.

Apparatus Required:

Sl. No. Apparatus/ Devices Rating/Quantity

1 OPAMP 741 IC 02
2 Power Supply +15V and -15V
3 Resistors 5.6k (6),1.8k, 22k(2)
4 Capacitor 0.5µF (1)
4 Diodes 02
5 Signal Generator 01
6 CRO 01
7 BNC connectors 02
8 Patch chords 20

Theory:
Clipper and Clamper circuits using diodes has a drawback of 0.7 forward voltage drop
which contributes in the output waveform. 741 OPAMP along with diodes can be used
to give precise output referring to Clamper and Clipper application. Precision clippers
consist of a dead zone circuit and a summing circuit. The dead zone circuit output is
summed with ‘Vi’ (input) to produce an output waveform with its positive half cycle
precisely clipped at Vref.

In the precision clamping application the op-amp circuit functions as an ideal diode. So,
this circuit can be regarded as the equivalent to conventional Clamper using diode with
an assumption that the diode is ideal diode with Vf equal to zero.
Diode clamping circuits those clamps the positive peak at zero, or at any bias voltage
(VB) can be realized using biasing arrangement.
Circuit Diagram:

Fig. No. 1: Precision Clipper

Design:

Precision clipper

Note: Diodes are used

Vref=I*R1

Vref=3V and I=500mA

R1= Vref/I =

R2=R3=R1=5.6KΩ

R4= R2||R3||R1=1.9KΩ [say 1.8K]

R5=R6=5.6KΩ R7=5.6KΩ
 Circuit Diagram

Fig. No. 2: Precision Clipper

Design:

Precision Clamper

RS Source Resistance =100Ω (assumed)

C1=1/2* RS*f=1/2*100*10KHz

C1=0.5µF

R1=VP/C1* Vf=5/0.5µF*0.05V*10KHz

=20KΩ [Std. value =22KΩ]

R1=R2= 22KΩ

Procedure

1. Check the components and patch cords.

2. Connections are made as per the circuit diagram.
3. Set the DC power supply of ±15V.
4. Apply an input signal (Sinusoidal) of specified value say 8volt (p-p) at 1 kHz.
5. Observe the input / Output waveforms on CRO.
Results/Waveforms:

Student Name USN Date Staff Signature

Experiment No.4

Design and Implementation of Differentiator and Integrator using 741 OPAMP

Objective: To design and demonstrate differentiator and Integrator using 741 OPAMP.

Apparatus Required:

Sl. No. Apparatus/ Devices Rating/Quantity

1 OPAMP 741 IC 02
2 Power Supply +15V and -15V
3 Resistors 270k, 12.5k,10k (3), 470Ω
4 Capacitor 0.05µF (1), 0.1µF (1)
5 Signal Generator 01
6 CRO 01
7 BNC connectors 02
8 Patch chords 20

Theory:
Differentiator circuit can be formed using OPAMP and passive elements as shown in Fig.
01. For triangular input it generates square wave output, Ramp function is converted in
step function. At very high frequencies circuit becomes unstable and oscillates.

Whereas Op-amp Integrator is an operational amplifier circuit that performs the

mathematical operation of integration, generated output voltage is proportional to the
integration of the input voltage; for Step input it gives Ramp output. Integrator circuit is
shown in Fig. 02.
Circuit Diagram:

Fig. No. 1: Differentiator

Design:
Circuit Diagram

Fig.2: Integrator

Design:
 Procedure

1. Check the components and patch cords.

2. Connections are made as per the circuit diagram.
3. Set the DC power supply of ±15V.
4. Apply an input signal Triangular/ Square wave of specified value say 4volt
(p-p) at 1 kHz.
5. Observe the input / Output waveforms on CRO.

Results/Waveforms:

Student Name USN Date Staff Signature

 Experiment No.5

Design and Implementation of R-C phase shift Oscillator using 741 OPAMP

Objective: To design and demonstrate R-C phase shift Oscillator using 741 OPAMP.

Apparatus Required:

Sl. No. Apparatus/ Devices Rating/Quantity

1 OPAMP 741 IC 01
2 Power Supply +15V and -15V
3 Resistors 6.8k (3),220k(1)
4 Potentiometer 10k (1)
4 Capacitor 2700pF (3)
6 CRO 01
7 BNC connectors 02
8 Patch chords 20

Theory:

RC phase shift oscillator generates sustained sinusoidal signal of known frequency in

range of Kilo Hertz. OPAMP inverting amplifier is used along with feed through RC filter
network, hence it is named as RC phase shift oscillator.

By varying the capacitor, the frequency of oscillations can be varied. The feedback RC
network gives a phase shift of 60 degrees each, hence total phase shift provided by the
three RC network is 180 degrees. The op amp is connected as inverting amplifier hence
the total phase shift around the loop will be 360 degrees. This condition is essential for
sustained oscillations. R & C components are selected to ensure total gain of 1, to satisfy
Barkhusain criteria.
Circuit Diagram

Fig.1: R-C Phase Shift Oscillator

Design:

I=50µA (I=100Ib)

Vomax= ± 11V (Considering ±12V Supply)

VR2=Vomax= 11 Volts
IR2= 11V, R2=220kΩ,

Gain of the amplifier =29 (Min)

R1= R2 /gain = 220kΩ/29 = 7.6kΩ , R1=6.8kΩ (std)

R1= R3=R4=6.8kΩ

C= 1/2πRf squrt(6)

C= 2700pF

Procedure

1. Check the components and patch cords.

2. Connections are made as per the circuit diagram.
3. Set the DC power supply of ±12V.
4. Vary the potentiometer in feedback path, until Sinusoidal wave is generated
at output terminal.
5. Observe the Output and feedback signals and phase shift on CRO.

Results/Waveforms:

Student Name USN Date Staff Signature

 Experiment No.6

Design and Implementation of Low pass 1st and 2nd Order Active Filter using 741
OPAMP

Objective: To design Low pass filter and compare the performance for 1st order and 2nd
order filter.

Apparatus Required:

Sl. No. Apparatus/ Devices Rating/Quantity

1 OPAMP 741 IC 01
2 Power Supply +15V and -15V
3 Resistors 120k (1),68k(2), 136k (1)
4 Capacitor 1300pF (1), 1600pF(1), 3300pF (1)
6 CRO 01
7 BNC connectors 02
8 Patch chords 20

Theory:

Capacitive reactance being function of the frequency becomes significant at low

frequency and draws the signal (signal pass), whereas at high frequencies it becomes
very small and attenuates the signal.

The performance of passive filter gets compromised under low resistance value for
load; to overcome this active component i.e. Opamp circuits can be used in amplifier
form.

The rate of attenuation after cutoff frequency for 1st and 2nd order can be compared, It is
40dB/ decade and 20dB/decade respectively, therefore the use of higher order circuit
for filter operation is justified.
Circuit Diagram

Fig.1: Low Pass Active Filter

Design:

R1=0.1VBE/ IBmax = 120kΩ

R1= R2=120 kΩ

Xc1=R1 at f1 (cut off frequency)

For f1 1 kHz C1= 1300pF

Procedure:

1. Check the components and patch cords.

2. Connections are made as per the circuit diagram.
3. Set the DC power supply of ±15V.
4. Set a sinusoidal input of fixed amplitude at mid frequency, Vary the input
frequency parameter over a range of kHz and note down the output
amplitude.
5. Determine gain in dB and plot gain versus frequency plot.
Circuit Diagram

Fig. 2: Second order active low pass filter

Design:

R1 + R2=0.1VBE/ IBmax = 140kΩ

R1= R2=68 kΩ

R3 = R1 + R2=136kΩ

Xc1=Squrt(2)xR2 at f1 (cut off frequency)

For f1 1kHz C1= 1600pF

C2=2C1

C2=3300pF
 Procedure

1. Check the components and patch cords.

2. Connections are made as per the circuit diagram.
3. Set the DC power supply of ±15V.
4. Set a sinusoidal input of fixed amplitude at mid frequency, Vary the input
frequency parameter over a range of kHz and note down the output
amplitude.
5. Determine gain in dB and plot gain versus frequency plot.

Results/Waveforms:

Student Name USN Date Staff Signature

 Experiment No.7

Design and Implementation of Triangular/Square wave Generator using 741

OPAMP (Back to Back system)

Objective: To design Triangular/square wave generator using 741 opamp and other
passive components.

Apparatus Required:

Sl. No. Apparatus/ Devices Rating/Quantity

1 OPAMP 741 IC 02
2 Power Supply +15V and -15V
3 Resistors 10k (1),270k(1), 47k (1) 1k(1)
4 Potentiometer 10k (1)
5 Capacitor 0.04 µF
6 CRO 01
7 BNC connectors 02
8 Patch chords 20
Theory

Two Opamps are used to form back to back systems. One opamp circuit uses capacitor
in a feedback path functioning as an integrator subjected to charging positively and
negatively depending upon input side force, resulting in to triangular wave at the
output. Resulting triangular wave signal is fed back as an input signal to non-inverting
Schmitt trigger circuits , Charging peak values are observed as UTP and LTP and
accordingly output of 2nd Opamp circuit switches between +Vsat and –Vsat, giving rise
to square wave.

Using potentiometer in series with R1 frequency of both the waveforms can be altered.

Diodes and potentiometers can be used in integrator circuit input line, to set unequal
duration for pulse-width and space –width to generate rectangular/saw-tooth
waveforms.
Circuit Diagram

Design

I=50µA,

C1= I*∆t/∆v, (Assume ∆t=….ms (Pulse/Space width)/∆v (5V))

R1= Vsat/ I

R2= Vsat / I

R2= 14V/50µA= 270k (std)

R3= UTP/I= 2.5/50µA =48k = (47k + 1k) std

 Procedure

1. Check the components and patch cords.

2. Connections are made as per the circuit diagram.
3. Set the DC power supply of ±15V.
4. Observe the output signals i.e. Output of an integrator and output of schmitt
trigger circuit.
5. Note down UTP/LTP and +Vsat/-Vsat levels of the output signal.

Results/Waveforms:

Student Name USN Date Staff Signature

 Experiment No.8

Design and Implementation of Astable Multivibrator using 741 OPAMP

Objective: To design astable multivibrator using 741 opamp and other passive
components.

Apparatus Required:

Sl. No. Apparatus/ Devices Rating/Quantity

1 OPAMP 741 IC 01
2 Power Supply +10V and -10V
3 Resistors 42.5k (1), 1M(1), 56k (1)
5 Capacitor 0.1 µF
6 CRO 01
7 BNC connectors 02
8 Patch chords 20

Theory:

The Op-amp Multivibrator is an astable oscillator circuit that generates a rectangular

output waveform using an RC timing network connected to the inverting input of the
operational amplifier and a voltage divider network connected to the other non-
inverting input.

Unlike the monostable or bistable, the astable multivibrator has two states, neither of
which are stable as it is constantly switching between these two states with the time
spent in each state controlled by the charging or discharging of the capacitor through a
resistor.

In the op-amp multivibrator circuit the op-amp works as an analogue comparator. An

op-amp comparator compares the voltages on its two inputs and gives a positive or
negative output depending on whether the input is greater or less than some reference
value, VREF.

However, because the open-loop op-amp comparator is very sensitive to the voltage
changes on its inputs, the output can switch uncontrollably between its positive, +V(sat)
and negative, -V(sat) supply rails whenever the input voltage being measured is near to
the reference voltage, VREF.

To eliminate any erratic or uncontrolled switching operations, the op-amp used in the
multivibrator circuit is configured as a closed-loop Schmitt Trigger circuit. Consider the
circuit below.
Circuit Diagram

Design:

Let UTP=0.5V

Assume R2=1M,

I= (Vsat – UTP)/ R2

I=8.5µA

IR3=VR3= UTP

R3= 56k

C1= 0.1µF

Pulse Width (t)= 500µS

I1=C1(UTP-LTP)/t

I1=200µA

R1=(Vo –UTP)/I1

R1=42.5k
 Procedure

1. Check the components and patch cords.

2. Connections are made as per the circuit diagram.
3. Set the DC power supply of ±10V.
4. Observe the output signals across capacitor and at opamp output terminal.
5. Note down UTP/LTP and +Vsat/-Vsat levels of the output signals.

Results/Waveforms:

Student Name USN Date Staff Signature