Op-amp Report 3e6335

“OPAMP APPLICATION TRAINER BOARD”

2011-2012 A Minor Project Report Submitted to Rajiv Gandhi Proudyogiki Vishwavidyalaya In partial fulfillment of the Degree of Bachelor of Engineering In Electronics & communication

Guided by: Mr. GANESH MUKATI (Sr. Lecturer) Mr. GAURAV DASONDHI (Lecturer) Electronics & communication Department

Submitted by: ANKIT GUPTA (0805EC091003) DEEPAK DASHORE (0805EC091017) GAURAV SINGH (0805ec091022) RITESH KUDEKAR (0805EC091064)

Department of Electronics &Communication JAWAHARLAL INSTITUTE OF TECHNOLOGY BORAWAN (KHARGONE), M.P.

JAWAHARLAL INSTITUTE OF TECHNOLOGY BORAWAN (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”, d to R.G.P.V. BHOPAL (M.P.)

Head of Department Mr. SANJAY CHOUHAN

Project Guide Mr. GANESH MUKATI Mr. GAURAV DASONDHI

Dr. ATUL UPADHYAY

Dr. D.K. PANDA

PRINCIPAL JIT Borawan, Khargone

DIRECTOR JIT Borawan, Khargone

JAWAHARLAL INSTITUTE OF TECHNOLOGY BORAWAN (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”, d 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 ing 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 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 Contents Page 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

. The principle of the 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 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:-

Vin

+ AVin

Ideal op-amp

Vout

~

−

Zout=0

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 20th 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 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 , particularly negative , 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 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, and

– is a function of both

and

due to the voltage divider formed by

. 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 .

:

a

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- 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 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 through the

– is a function of

network.

and

because of the negative

form a voltage divider, and as

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

– is a high-

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 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 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 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 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

For power supply • • • • •

Transformer Bridge rectifier IC 7812 IC 7912 capacitors

• Power cable • Ceramic capacitor

• • • • • • • •

12V , .5 amp 100V ,2 amp For +ve regulator For - ve regulator 2200 uF (2) 220 uF, 35V (2) 1 .1 uF , (4)

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 Deg: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 opamp 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 OPAMP.

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