Operational Amplifiers - Mathematical Operations,
Addition, Subtraction, Differentiator, Integrator
IFE - TU Graz
In our previous, we discussed the basics of operation amplifier circuits with negative feedback.
We learned that these circuits can amplify the input signal by multiplying it with a constant
factor known as the gain. However, operation amplifiers can be used for a variety of
mathematical operations. In this video, we will explore more complex operations implemented
with electronics.
Inverting Amplifier
The inverting amplifier is the counterpart of the circuit we discussed last time. It consists of an
input resistor (Re) connected to the inverting input and a feedback resistor (Ra) connected to the
inverting input as well. To determine the output voltage (Va) as a function of the input voltage
(Ve), we can apply the rules we learned. By solving the loop equations, we find that the amplifier
has a gain (G) equal to -Ra/Re.
Analog Summing Amplifier
The analog summing amplifier is similar to the inverting amplifier, but with an additional input
resistor (Re2). We can use the superposition principle to analyze the impact of each individual
voltage and current source on the output voltage. By applying the rules for negative feedback
amplifiers, we can simplify the circuit and calculate the output voltage.
Differential Amplifier
The differential amplifier gives an output voltage proportional to the difference between two
input voltages. Again, we use the superposition principle to analyze the circuit for each input
voltage. By applying the rules for noninverting and inverting amplifiers, we can calculate the
output voltage as the difference between the two individual output voltages.
Differentiator
The differentiator is an inverting amplifier with a capacitor at the input instead of a resistor. By
applying the current-voltage relation of the capacitor, we can calculate the output voltage as the
derivative of the input voltage. The output voltage can be scaled by the product of the resistor
(Ra) and capacitor (Ce) values.
Integrator
Addition, Subtraction, Differentiator, Integrator
IFE - TU Graz
In our previous, we discussed the basics of operation amplifier circuits with negative feedback.
We learned that these circuits can amplify the input signal by multiplying it with a constant
factor known as the gain. However, operation amplifiers can be used for a variety of
mathematical operations. In this video, we will explore more complex operations implemented
with electronics.
Inverting Amplifier
The inverting amplifier is the counterpart of the circuit we discussed last time. It consists of an
input resistor (Re) connected to the inverting input and a feedback resistor (Ra) connected to the
inverting input as well. To determine the output voltage (Va) as a function of the input voltage
(Ve), we can apply the rules we learned. By solving the loop equations, we find that the amplifier
has a gain (G) equal to -Ra/Re.
Analog Summing Amplifier
The analog summing amplifier is similar to the inverting amplifier, but with an additional input
resistor (Re2). We can use the superposition principle to analyze the impact of each individual
voltage and current source on the output voltage. By applying the rules for negative feedback
amplifiers, we can simplify the circuit and calculate the output voltage.
Differential Amplifier
The differential amplifier gives an output voltage proportional to the difference between two
input voltages. Again, we use the superposition principle to analyze the circuit for each input
voltage. By applying the rules for noninverting and inverting amplifiers, we can calculate the
output voltage as the difference between the two individual output voltages.
Differentiator
The differentiator is an inverting amplifier with a capacitor at the input instead of a resistor. By
applying the current-voltage relation of the capacitor, we can calculate the output voltage as the
derivative of the input voltage. The output voltage can be scaled by the product of the resistor
(Ra) and capacitor (Ce) values.
Integrator
