Operational Amplifier
Op-Amp and its application in closed loop system
· Familiarization with summing amplifier module.
· To kn0w its usage in servo motor trainer.
Equipment Required:
Summing Amplifier
Potentiometer(U-157)
Servo motor(U-161)
Power supply(U-156)
Techo meter(U-159)
Techo amp unit(U-155)
Motor driver(U-154)
Function generator(U-162)
Oscilloscope
Operation amplifier(U-153)
Attenuator(U-151)
Theory:
Operational Amplifier:
An Operational Amplifier or op-amp is a voltage amplifying device designed to be used with external feedback components such as resistors and capacitors between its output and input terminals. It is a high-gain electronic voltage amplifier with a differential input and usually a single-ended output. Op-amps are among the most widely used electronic devices today, being used in a vast array of consumer, industrial, and scientific devices.
Op-amp operation:
The amplifier’s differential inputs consist of a non-inverting input with voltage (V+) and an inverting input with voltage (V−). Ideally, an op-amp amplifies only the difference in voltage between the two, also called differential input voltage. The output voltage of the op-amp Vout is given by the equation,
Vout = AOL (V+ – V–)
Summing Amplifier:
The term summing amplifier is also named as adder, which is used to add two signal voltages. The circuit of the voltage adder is so simple to construct and it enables to add many signals together. These kind of amplifiers is used in a wide range of electronic circuits. For instance, on a precise amplifier you have to add a small voltage to terminate the offset error of the operational amplifier. An audio mixer is another example to add the waveforms together from various channels before sending the mixed signal to a recorder. You can add or change the i/p or the gain without messing up with the i/ps of the gain. Just recollect that the circuit of the inverting summing amplifier changes the input signals.
Summing Amplifier