____________________________________________________

FACULTY OF TECHNICAL AND VOCATIONAL

EDDUCATION

BBV30303 ELECTRONIC 2

EXPERIMENT REPORT 5

(OP AMPLIFIER- Inverting Amplifier)

MEMBER GROUP

BIL NAMA MATRIK

1. Azman Bin Hanafiah DB120004

2. Muhammad Nazmy Bin Zulkifli DB120075

Check By:

Dr. Alias Bin Masek

Pensyarah Elektronik II

Submit: 13/12/2014

1.0. TITLE

OP AMP - Inverting Amplifier

2.0. AIM

To improve our knowledge about Inverting Amplifier

3.0. OBJECTIVES

3.1. To understand the Operation of Amplifier with Inverting

3.2. To record their result form in oscilloscope

3.3. To analysis differentiation wave in Vin form and Vout form.

4.0. EQUIPMENTS

4.1. KL-200 Linear Circuit Lab.

4.2. Experiment module: KL-23013

4.3. Instrument experiment:

4.3.1. Voltmeter

4.3.2. Oscilloscope

4.3.3. Signal generator

4.4. Basic hand tools.

5.0. THEORY

An op-amp is a high gain, direct coupled differential linear amplifier choose response

characteristics are externally controlled by negative feedback from the output to input, op-amp

has very high input impedance, typically a few mega ohms and low output impedance, less than

100. Op-amps can perform mathematical operations like summation integration,

differentiation, logarithm, anti-logarithm, etc., and hence the name operational amplifier op-

amps are also used as video and audio amplifiers, oscillators and so on, in communication

electronics, in instrumentation and control, in medical electronics, etc.

5.1. INVERTING OPERATIONAL AMPLIFIER CONFIGURATION

- In this Inverting Amplifier circuit the operational amplifier is connected with feedback

to produce a closed loop operation.

- When dealing with operational amplifiers there are two very important rules to

remember about ideal inverting amplifiers, these are: No current flows into the input

terminal and that V1 always equals V2. However, in real world op-amp circuits

both of these rules are slightly broken.

- This is because the junction of the input and feedback signal ( X ) is at the same

potential as the positive ( + ) input which is at zero volts or ground then, the junction

is a Virtual Earth.

- Because of this virtual earth node the input resistance of the amplifier is equal to the

value of the input resistor, Rin and the closed loop gain of the inverting amplifier can

be set by the ratio of the two external resistors.

- We said above that there are two very important rules to remember about Inverting

Amplifiers or any operational amplifier for that matter and these are.

a. No Current Flows into the Input Terminals

b. The Differential Input Voltage is Zero as V1 = V2 = 0 (Virtual Earth)

6.0. PROCEDURE

Experiment procedure:

i) Insert the short-circuit clip by referring to figure 15-11 (a) and the short-circuit clip

arrangement diagram 23013-block b.1.

ii) Connected the signal generator to the input terminal (IN1), then adjust the output

of the signal generator to 1KHz sine wave. Slowly increase the amplitude so that

the maximum non-distorted waveform in the output terminal can be displayed

(used the oscilloscope to measured).

iii) Record the waveforms of Vin 1 and Vout.

iv) Disconnect the output from the signal generator by removing the short-circuit clip,

then connect the input terminal to ground. Use the DCV scale of the multimeter

(or oscilloscope) to measure the DC level at the output terminal, then make

records.

v) Insert the short-circuit clip by reffering to fig 15-11 (b), in which the inverting

amplifier with offset is connected, and the short-circuit clip arrangement diagram

23013-block b.1.

vi) Repeat step (2) and (3).

vii) Randomly adjust VR100K (VR3), then view if the output wave form will be

changed.

viii) Disconnect the output from the signal generator by removing the short-circuit clip,

then connect the input terminal to ground. Use the DCV scale of the multimeter

(or oscilloscope) to measure the DC level at the output terminal. If the DC level is

not 0V, please adjust VR100K (VR3) so that this level will be 0V.

ix) Repeat step (2) and (3).

x) Compare the output DC levels and waveforms between the circuits with offset

and without offset.

7.0. RESULT

RESULT FOR INVERTING OP-AMPLIFIER

POSITION WAVEFORM VPP Vout

(DCV)

Without

offset

256mV

250mV

117mV

1200mV

With offset

568mV

600mV

1.47V

1500mV

8.0. DISCUSSION OR ANALYSIS

Some knowledge about the experiment:

i. Based on the experiment we will to know about Operation Amplifier. OP-Amp is a

three-port device having two inputs and one output. It was invented to simplify

the design of inverting and non-inverting DC amplifiers by the simple control of

external negative feedback.

ii. This deceptively simple building block is to analog electronics what nand or nor

gates are to digital electronic circuits: it reduces analog circuit design to a simple

problem of determining suitable external feedback and interconnecting networks

without the complication of having to know what's going on inside the op-amp

itself.

iii. Treating the op-amp as ideal is often all that is necessary to use it in practice,

provided we skillfully appreciate the limitations imposed by basic device

parameters that would typically include: non-infinite open-loop gain, frequency

response expressed by slew rate, single-pole roll-off frequency and its related

gain-bandwidth product GBP, non-infinite input port resistances and non-zero

output resistance; power-supply limiting or railing due to finite power supply

voltages.

iv. Although the op-amp is employed in a truly impressive array of many different

circuits, all are based in part on one or both of the following two fundamental

circuit configurations, the inverting and non-inverting DC amplifiers. You will gain

an appreciation of the power of the op-amp as a basic building block along with

some of its inherent limitations by investigation of these two basic circuits.

8.1. The Ideal Op-Amp

The ideal behavior of an op-amp implies that

a) The output resistance is zero

b) The input resistance seen between the two input terminals (called the

differential input resistance) is infinity.

c) The input resistances seen between each input terminal and the ground

(called the common mode input resistance) are infinite.

d) Op-amp has a zero voltage offset ie., for V1 = V2 = 0, output voltage VO

= 0.

e) Common mode gain AC is zero.

f) Differential mode gain, Ad is infinity.

g) Common Mode Rejection Ratio (CMRR) is infinity.

h) Bandwidth is infinite.

i) Slew rate is infinite.

- We can look the differentiation at the diagram below:

9.0. CONCLUSION

Based on the experiment i can understand about the operation Amplifier in Inverting

form. After that, we have get the comparison on DC levels and waveforms between the

circuits with offset and without offset.

10.0. EXPERIMENT ACTICITY (PICTURE)

Figure 1: Connections for inverting OP Amplifier

Figure 1: Using Oscilloscope to measure the sine wave for input OP Amplifier

Figure 3: Using Oscilloscope to measure the sine wave for Output Inverting OP Amplifier.