“OPAMP APPLICATION TRAINER BOARD”

2011-2012A Minor Project Report Submitted to

Rajiv Gandhi Proudyogiki Vishwavidyalaya In partial fulfillment of the

Degree of Bachelor of EngineeringIn

Electronics & communication

Guided by: Submitted by:Mr. GANESH MUKATI ANKIT GUPTA(Sr. Lecturer) (0805EC091003)Mr. GAURAV DASONDHI DEEPAK DASHORE

(Lecturer) (0805EC091017) Electronics & communication Department GAURAV SINGH (0805ec091022) RITESH KUDEKAR (0805EC091064)

Department of Electronics &CommunicationJAWAHARLAL INSTITUTE OF TECHNOLOGY

BORAWAN (KHARGONE), M.P.

JAWAHARLAL INSTITUTE OF TECHNOLOGYBORAWAN (KHARGONE), M.P.

CERTIFICATE

This is to certify that minor project entitled “OPAMP APPLICATION BREAD BOARD TRAINER” is submitted by “Ankit Gupta, Deepak Dashore, Gaurav Singh, Ritesh Kudekar” students of Third year of “Electronics & Communication” year 2011-2012 in partial fulfillment of the requirements of “Rajiv Gandhi Proudyogiki Vishwavidyalaya Bhopal” for the award of the Degree of Bachelor of Engineering in Electronics & Communication branch of “Jawaharlal Institute of Technology”, affiliated to R.G.P.V. BHOPAL (M.P.)

Head of Department Project GuideMr. SANJAY CHOUHAN Mr. GANESH MUKATI Mr. GAURAV DASONDHI

Dr. ATUL UPADHYAY Dr. D.K. PANDA PRINCIPAL DIRECTOR

JIT Borawan, Khargone JIT Borawan, Khargone

JAWAHARLAL INSTITUTE OF TECHNOLOGYBORAWAN (KHARGONE), M.P.

CERTIFICATE OF APPROVAL

This is to certify that minor project entitled “OPAMP APPLICATION BREAD BOARD TRAINER” is submitted by “Ankit Gupta, Deepak Dashore, Gaurav Singh, Ritesh Kudekar” in partial fulfillment of the requirements for the award of Bachelor of Engineering in Electronics & Communication branch during the academic year 2011-2012 from “Jawaharlal Institute of Technology”, affiliated to R.G.P.V. BHOPAL (M.P.)

External Examiner: Internal Examiner:

ACKNOWLEDGEMENT

We the students of third year of electronics and communication engineering are really thankful to our Lecturers team for guiding us so precisely, so we can take the challenge on such ambitious project of advanced security systems. We always thankful to Mr. Sanjay Chouhan, Head of Department (Electronics and Communication Engg.) for cooperation and trust which they shown in us and for supporting us in this project, so we can focus on the target.

We are thankful to our Project Guide Mr. Ganesh Mukati and Mr. Gaurav Dasondhi for such a devoted guidance on our project and showing faith in our project, their instructions are like the guiding light on the path of the excellence of our graduation period. We also thankful to, Mr. Yogendra Singh Patel, for the constantly working on potential of the students and always telling them what is the right way to solve the problems, they are our inspiration for solving the problems at the professional level. We are also really thankful to, Mr. Girijesh Dasoundhi and all the faculty members for being shining stars of our night sky. In the end we are thankful Dr. Atul Upadhyay , Principal (J.I.T, Borawan), and Dr. D.K. Panda Director (J.I.T, Borawan) for providing us such good operative

ANKIT GUPTA DEEPAK DASHORE GAURAV SINGH RITESH KUDEKAR

Abstract

“OPAMP APPLICATION TRAINER BOARD”

Operational amplifier is usually Called Op Amps. An amplifier is a device that accepts a varying input signal and produces a similar output signal with a larger amplitude.

They are the basic components used to build analog circuits. The name “operational amplifier” comes from the fact that they were originally used to perform mathematical operations such as integration and differentiation.

We also easily perform its application on bread board trainer and check that our project will successes or not. So we show on this project the various application of opamp using bread board trainer.

Applications: • Inverting amplifier• Non-inverting amplifier• Summing amplifier• Comparator• Integrator• Differentiator

This project is very less expensive, so we get good benefits of this project.

Table of ContentsPage No.

Chapter-1 INTRODUCTION

Chapter-2 BASIC THEORY

Chapter-3 HARDWARE IMPLEMENTATION

3.1 Block Diagrams of op-amp

3.2 Description of Block Diagrams

3.3 Op-amp applications

3.4 Circuit Components

3.5 PCB Layout

3.6 PCB Design Techniques

Chapter-4 CONCLUSION

4.1 Advantages of op-amp application

4.2 Limitations of op-amp application

4.3 Application of Project

4.4 Future Enhancement

Chapter-5 References :

Chapter-1 INTRODUCTION:

Operational amplifier is usually Called Op Amps. An amplifier is a

device that accepts a varying input signal and produces a similar output signal with a

larger amplitude.

An operational amplifier  is a DC-coupled high-gain electronic voltage amplifier with

a differential input and, usually, a single-ended output.  An op-amp produces an output

voltage that is typically hundreds of thousands times larger than the

voltage difference between its input terminals

. Op amps are high gain amplifiers, and are used almost invariably with overall loop

feedback. The principle of the feedback amplifier has to rank as one of the more notable

developments 20th century— right up there with the automobile or airplane for breadth

of utility , and general value to engineering. And, most importantly, such feedback

systems, although originally conceived as a solution to a communications problem,

operate today in more diverse situations. This is a clear tribute to the concept’s

fundamental value.

Circuit Notation of OP-AMP:-

AN IDEAL OP-AMP:-

+

~

AVin

Vin Vout

Zout=0

Ideal op-amp

Op-amps are one of the basic building blocks of Analogue Electronic

Circuits. Operational amplifiers are linear devices that have all the properties required for

nearly ideal DC amplification and are therefore used extensively in signal conditioning.

filtering or to perform mathematical operations such as add, subtract, integration and

differentiation.

An ideal Operational Amplifier is basically a three-terminal device which consists of two

high impedance inputs, one called the Inverting Input, marked with a negative or "minus"

sign, ( "-" ) and the other one called the Non-inverting Input, marked with a positive or

"plus" sign ( "+" ).

Chapter-2 BASIC THEORY:

A final major transitional phase of op amp history began with

the development of the first IC op amp, in the mid 1960’s. Once IC technology became

widely established, things moved quickly through the latter of the 20 th century years, with

milestone after milestone of progress being made in device performance. This story

begins back in the vacuum tube era and continues until today (2002).

The Operational Amplifier (Op Amp) can be used in many different ways. The Op-amp

has two inputs an inverting input (-) and a non-inverting input (+) and one output. A

signal applied to the inverting input will have its polarity reversed on the output. A signal

applied to the non-inverting input will retain its polarity on the output. The gain or

amplification of the signal is determined by a feedback resistor that feeds some of the

output signal back to the inverting input .The smaller the resistor, the lower the gain.

Some typical op-amp pin outs are shown below. The most common are the 741 and 1458

dual op-amp.

The operational amplifier is arguably the most useful single device in analog electronic

circuitry. With only a handful of external components, it can be made to perform a wide

variety of analog signal processing tasks. It is also quite affordable, most general-purpose

amplifiers selling for under a dollar apiece. Modern designs have been engineered with

durability in mind as well: several "op-amps" are manufactured that can sustain direct

short-circuits on their outputs without damage.

One key to the usefulness of these little circuits is in the engineering principle of

feedback, particularly negative feedback, which constitutes the foundation of almost all

automatic control processes. The principles presented here in operational amplifier

circuits, therefore, extend well beyond the immediate scope of electronics. It is well

worth the electronics student's time to learn these principles and learn them well.

Pin Diagram of an OP-AMP:-

LM741 Operational Amplifier: Circuit Architecture:-

Chapter-3 HARDWARE IMPLEMENTATION

3.1 Block Diagram of op-amp:

3.2 Description of Block Diagram:

An operational amplifier is a direct-coupled high-gain

amplifier usually consisting of one or more differential amplifiers and usually followed

by a level translator and an output stage. The output stage is generally a push-pull

symmetry pair. An op-amp is available as a single integrated ckt package.

An op-amp is a high quality amplifier. It contains four stages, which are connected in

cascaded manner.

The first stage of an op.amp is a double ended differential amplifier. This stage provides

maximum voltage gain. This stage should employ a current source at the common emitter

node for good common mode rejection.

This second stage is an intermediate gain stage called single ended differential amplifier.

It does not require a current source in the emitter. Normally the second stage is needed

only to provide some additional gain. Its input resistance should be relatively high to

prevent excessive loading of the first stage.

The third stage is an emitter follower, which produces unity gain. It has high input

resistance and also low output resistance. It matches the output of amplifier stage and the

input of output stage.

The fourth stage is a level translator and output driver. This stage is used for preventing

any undesired dc current in the load and increasing the permissible output voltage swing.

Hence it supplies large output voltage or current

3.3 Op-amp Applications is -

• Inverting amplifier

• Non-inverting amplifier

• Summing amplifier

• Comparator

• Integrator

• Differentiator

Inverting amplifier:

An inverting amplifier inverts and scales the input signal. As long as

the op-amp gain is very large.

The amplifier gain is determined by two stable external resistors (the feedback resistor Rf

and the input resistor Rin) and not by op-amp parameters which are highly temperature

dependent

As with the non-inverting amplifier, we start with the gain equation of the op-amp:

This time, – is a function of both and due to the voltage divider formed by

a and . Again, the op-amp input does not apply an appreciable load, so:

Substituting this into the gain equation and solving for :

If is very large, this simplifies to

.

In particular, the Rin–Rf resistor network acts as an electronics) where the inverting (i.e.,

−) input of the operational amplifier is like a fulcrum about which the seesaw pivots. That

is, because the operational amplifier is in a negative-feedback configuration, its internal

high gain effectively fixes the inverting (i.e., −) input at the same 0 V (ground) voltage of

the non-inverting (i.e., +) input, which is similar to the stiff mechanical support provided

by the fulcrum of the seesaw. Continuing the analogy.

Non-inverting amplifier:

The gain equation for the op-amp is:

However, in this circuit – is a function of because of the negative feedback

through the network. and form a voltage divider, and as – is a high-

impedance input, it does not load it appreciably. Consequently:

where

Substituting this into the gain equation, we obtain:

Solving for :

If is very large, this simplifies to

.

Non-inverting amplifier Amplifies a voltage (multiplies by a constant greater than 1).

The input impedance is at least the impedance between non-inverting ( + ) and inverting (

− ) inputs, which is typically 1 MΩ to 10 TΩ, plus the

impedance of the path from the inverting ( − ) input to ground (i.e., R1 in

parallel with Rf). Because negative feedback ensures that the non-inverting and inverting

inputs match, the input impedance is actually much higher.

The non-inverting ( + ) and inverting ( − ) inputs draw small leakage

currents into the operational amplifier. These input currents generate

voltages that act like unmodeled input offsets. These unmodeled

effects can lead to noise on the output.

Summing amplifier:

The summing amplifier is a handy circuit enabling you to add several signals

together. What are some examples? If you're measuring temperature, you can add a

negative offset to make the display read "0" at the freezing point. On a precision

amplifier, you may need to add a small voltage to cancel the offset error of the op amp

itself. An audio mixer is another good example of adding waveforms (sounds) from

different channels (vocals, instruments) together before sending the combined signal to a

recorder.

Although, there are many ways to make a summer, this one is nice because it keeps the

interaction between inputs at a minimum. What does that mean for you the designer? You

can change the gain or add another input without messing with the gains of the other

inputs. Just remember that the circuit also inverts the input signals. Not a big deal. If you

need the opposite polarity, put an inverting stage before or after the summer.

Comparator:

In electronics, a comparator is a device that compares two voltages or

currents and switches its output to indicate which is larger. They are commonly used in

devices such as Analog-to-digital converters.

A comparator is designed to produce well limited output voltages that easily interface

with digital logic. Compatibility with digital logic must be verified while using an op-

amp as a comparator. An operational amplifier (op-amp) has a well balanced difference

input and a very high gain. This parallels the characteristics of comparators and can be

substituted in applications with low-performance requirements. Many op-amps have back

to back diodes between their inputs. Op-amp inputs usually follow each other so this is

fine. But comparator inputs are not usually the same. The diodes can cause unexpected

current through inputs.

Differentiator:

The differentiator as its name implies, the circuit performs the

mathematical operation of differentiation ; that is the output waveform is the derivative of

the input waveform. The differentiator may be constructed from basic inverting amplifier

if an input resistor R1 is replaced by a capacitor C.

The output V0 is equal to the RfC times the negative instantaneous rate of change of the

input voltage Vin with time. Since the differentiator performs the reverse of the

integrator’s function, a cosine wave input will produce a sine wave output, or a triangular

input will produce a square wave output.

A differentiator circuit consists of an operational amplifier, resistors are used at

feedback side and capacitors are used at the input side. The circuit is based on the

capacitors current to voltage relationship:

where I is the current through the capacitor, C is the capacitance of the capacitor, and

V is the voltage across the capacitor. The current flowing through the capacitor is

then proportional to the derivative of the voltage across the capacitor. This current

can then be connected to a resistor, which has the current to voltage relationship:

where R is the resistance of the resistor.

If Vout is the voltage across the resistor and Vin is the voltage across the capacitor, we

can rearrange these two equations to obtain the following equation.

Integrator:

The integrator is a circuit in which the output voltage waveform is the

integral of the input voltage waveform . such a circuit is obtained by using a basic

inverting amplifier configuration if the feedback resistor Rf is replaced by a capacitor Cf.

Output equation indicates that the output voltage is directly proportional to the negative

integral of the input voltage and inversely proportional to the time constant R1Cf. For

example ,if the input is a sine wave, the output will be a cosine wave; or if the input is a

square wave, the output will be a triangular wave.

3.4 Circuit Components:

For op-amp application trainer kit

• Op-amp IC• Resistors• Variable resistor• Ceramic capacitors

• Switch • Banana socket

• LM 741 CN• 10 K (6)• 10 K (2)• .1 uF (3)• 1 uF (1)

• 2 mm

3.5 Power supply:

The objective here is to build a dual power supply that generates regulated

+12 volts and -12 volts from 230VAC mains. Such a supply is a very common

requirement in all those circuits that use op-amps. Since op-amps are very widely used in

a variety of circuits of hobbyists’ interests, construction of this project could serve as a

very useful tool in testing all those circuits that need a dual supply. Each of the outputs in

the circuit shown in Fig.8.1 has a current delivering capability of 250mA. You would

also discover this circuit to be an integral part of the more complex circuits that are mains

operable.

Circuit diagram of power supply:

PCB layout:

3.6 PCB DESIGN TECHNIQUES:-

PCB Designing:-

We have taken a blank copper PCB, then we have designed layout

using Express PCB software. After that we have printed the layout of the power supply

on the blank copper PCB, Then drilled the appropriate holes.

Chemical etching Process:-

Now the printed PCB is taken for etching process. The PCB is dropped in the solution of

Hydrochloric Acid (HCL) and Sulphuric Acid

Soldering:- In the soldering process all the circuit components are soldered onto the

PCB. Soldering process requires soldering wire and soldering iron along with the

components which are to be soldered.

Chapter-4 CONCLUSION

4.1 Advantages:-

Op-amps are made of transistors. The advantages of using op-amps as gain

blocks instead of simpler transistor circuits is usually simpler design made with fewer

mounted parts (even though the total device count is higher, considering the complexity

inside the op-amps) and more ideal and predictable performance, often at lower supply

current. There are exceptions, where individual transistors are more suited to the desired

functions, when higher frequencies, larger currents, voltages or higher power are

involved. Also, if cost is more important than ideal performance, transistor designs can

often beat op-amp ones, even though there are some very low cost op-amps available.

4.2 Limitations of op-amp:-

The primary limitation of op-amp is that they are not especially fast: The typical

performance degrades rapidly for frequencies greater than about 1 MHz, although some

models are designed specially to handle higher frequencies.

4.3 Application of Project:-

This operational amplifier kit can be used in electronics labs to

understand the basic operations performed by OP-AMP. It is easy to handle and easily

under stable by the students who are willing to understand the basic applications of OP-

AMP.

chapter-5 REFERENCES

Websites:

http://www.ti.com/product/LM741

www.electronics world.com

www.opamp circuits.com

Books:

A.N. Gayakwad , op-amp integration

Jacob Milllman & Halkias , Integrated Electronics

R.S. Sedha, Applied electronics