UNIVERSAL COLLEGE OF ENGG. AND TECH.

ANALOG ELECTRONICS

AIM: OP-AMP AMPLIFICATION, DC AND AC AMPLIFIERS, SCALING AND SUMMING

AMPLIFIERS

Prepared By:

Group:- 12 (C)

Devansh Dave 130460109011

Parita Bhavsar 130460109007

Guided By:

Prof. Kapil Dave

FLOW OF PRESENTATION

• Op-Amp• TERMINOLOGY• 741 Op-Amp• Schematic Diagram of Op-Amp• Inverting Amplifiers• Non-Inverting Amplifiers• Summing Amplifiers• Scaling Amplifiers

OP-AMP

• Op-Amp-An active circuit element designed to perform mathematical operations of addition, subtraction, multiplication, division, differentiation and integration.

• High performance linear amplifier that requires a power source to operate.

TERMINOLOGY

• Gain- Amount of amplification produced by an Op-Amp. Gain is independent from the supply voltage (power given for the Op-Amp to operate).

• Open-Loop Mode-Function of an Op-Amp when the feedback resistor (Rf) is zero. The Op-Amp operates as a comparator and not as a linear amplifier.

TERMINOLOGY

• Comparator-Compares the –V and +V inputs to see which is greater and returns a result.

• Bandwidth-The range of frequency at which an Op-Amp will function. (Ideal = ∞)

TERMINOLOGY

• Slew Rate (V/µs)- Amount of time it takes for the Op-Amp to step to another voltage level. (Non-Ideal)

• Input Offset Voltage- Even when there is no input voltage the Op-Amp gives off a small voltage. This can be canceled out by use of the Offset Null pin on the chip. (Non-Ideal)

• Common Mode Rejection Ratio (CMRR)- Ability of an Op-Amp to reject a signal applied to both inputs simultaneously.

741 OP-AMP

Maximum Ratings

Supply Voltage ±18 VPower Dissipation 500 mWDiff. Input Voltage ±30 VInput Voltage ±15 VOperating Temperature 0°C to 70°C

Characteristics

Input Offset Voltage 2 to 6 mVInput Resistance .3 to 2 MΩCMMR 70 to 90 dBBandwidth .5 to 1.5 MHzSlew Rate .5 V/µs

1

2

3

4 5

6

7

8

-

+

- INPUT

+ INPUT

- V

Output

Offset Null

+ V

Offset Null

No Connection

Schematic Diagram of 741 OP-AMP

OP-AMP TYPES

Op-amp DC

AC

DC OP-AMPS

• In DC op-amps, the output signal changes in response to changes in its DC input levels.

• A DC amplifier can be inverting, non-inverting or differential.

• Let us see them in detail

INVERTING OP-AMP

• Here the inverting circuit diagram of Op-Amp is shown,

INVERTING OP-AMP

• The input is given to the Inverting terminal of Op-Amp so we get an Inverted output with 180° phase difference and out of phase.

NON-INVERTING OP-AMP

NON INVERTING AMPLIFIER

• The input signal is given to non-inverting terminal of Op-Amp. The output is without any phase difference and in phase to input.

DIFFERENTIAL AMPLIFIER

If R1 = R2 and Rf = Rg:

DIFFERENTIAL AMPLIFIER

• It amplifies the difference between two voltages but does not amplify the particular voltages.

• Where Vin+ and Vin

- are the input voltages and Ad is the differential gain

SUMMING AMPLIFIER

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SCALING AMPLIFIER

REFERENCES

• Ramakant A Gayakwad, Op-Amps and Linear integrated circuits, Prentice Hall of India

• K.R.Botkar, Integrated Circuits, Khanna Publishers

• www.google.com• www.wikipedia.org

THANK YOU