4/11/2012
Op Amp
Applications
Chapter 6
Op−Amp
Applications
4th
Spring 2012
Semester Mechatronics
SZABIST, Karachi
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CH 6
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Op Amp
Applications
Course Support
humera.rafique@szabist.edu.pk
Office: 100 Campus (404)
Official: ZABdesk
Subsidiary:
https://sites.google.com/site/zabistmechatronics/home/spring-2012/ecd
ebooks:
https://sites.google.com/site/zabistmechatronics/home/ebooks
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4/11/2012
Chapter Contents
Op Amp
Applications
3
• Constant gain multiplier
• Voltage summing
• Voltage buffer
• Controlled Sources*
• Active filters
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Op Amp
Applications
Constant Gain
Multiplier
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Op Amp
Applications
Constant Gain Multiplier
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Constant Gain Multiplier:
Inverting
Non-inverting
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Op Amp
Applications
CH 6
Constant Gain Multiplier
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Example 11.1:
Determine the output voltage
for the circuit with a sinusoidal
input of 2.5 mV.
Example 11.2:
Calculate the output voltage
from the given circuit for an
input of 120 µV.
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Op Amp
Applications
Constant Gain Multiplier
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Multistage Constant Gain Multiplier:
Cascade
A = A1A 2 A 3
 R
A = 1 + f
 R1
 Rf  Rf 
 −
−

  R2   R3 
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Op Amp
Applications
CH 6
Constant Gain Multiplier
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Multistage Constant Gain Multiplier:
Parallel
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Op Amp
Applications
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Constant Gain Multiplier
Example 11.3:
Calculate the output voltage using the circuit for resistor components of value Rf =
470 kΩ, R1 = 4.3 kΩ, R2 = 33 kΩ, and R3 = 33 kΩ for an input of 80 µV.
Example 11.4:
Show the connection of an LM124 quad op-amp as a three-stage amplifier with gains
of 10, 18, and 27. Use a 270-k Ω feedback resistor for all three circuits. What output
voltage will result for an input of 150 µV?
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Op Amp
Applications
CH 6
Constant Gain Multiplier
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Example 11.5:
Show the connection of three op-amp stages using an
LM348 IC to provide outputs that are 10, 20, and 50
times larger than the input. Use a feedback resistor of
Rf = 500 kΩ in all stages.
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Op Amp
Applications
Voltage
Summing
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Applications
CH 6
Voltage Summing
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Voltage Summing Amplifier:
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Op Amp
Applications
Voltage Summing
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Voltage Subtraction Amplifier:
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Applications
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Voltage Summing
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Single stage Voltage Subtraction Amplifier:
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Op Amp
Applications
Voltage Summing
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Example 11.6:
Calculate the output voltage for the circuit. The
inputs are V1 = 50 sin(1000t) mV and V2 = 10
sin(3000t) mV.
Example 11.7:
Calculate the output voltage for the circuit. The inputs are V1 = 50 sin(1000t) mV
and V2 = 10 sin(3000t) mV.
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Op Amp
Applications
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Voltage Summing
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Example 11.8:
Determine the output voltage:
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