Anonymous
Anonymous asked in Science & MathematicsPhysics · 7 years ago

# Operational amplifier?

what is operational amplifier how it is used for inverting and non inverting signals . class 12th phy.

Relevance

An operational amplifier produces an output voltage that is some point between it's positive and negative power supply voltages. An ideal op-amp has no offset, ie the point of transition between a positive and negative output is when the two inputs are at the same voltage. The input differential required to drive the output completely to one supply or the other is very small, so if the negative input is connected to feedback from the output, the output will move to the point where the the two inputs are (almost) the same voltage. So if the feedback is a attenuator, the output will be (almost) exactly the inverse of the feedback attenuator, ie the feedback attenuator (resistors) accurately defines the amplifier gain.

If the positive input is connected to zero/ground, any current via a resistor to the negative input will be removed buy an opposite current from the feedback network, making an inverting amplifier.

The stability of feedback is a mathematically complicated issue, commonly referred to as frequency compensation. Generally speaking, amplifier delays produce a phase shift which can change negative feedback into positive feedback at higher frequencies, resulting in oscillations. The general solution is to make one delay so dominant that it wastes all the amplifier gain at a frequency below where other delays begin to add their delays. Each delay, aka pole, can at most add 90 degrees of phase shift , but the loss of gain continues as the frequency rises. So if the dominant pole has wasted all the amplifier gain before the other circuit poles can add another 90 degrees, then the feedback will be stable.

http://en.wikipedia.org/wiki/Op-amp

• Login to reply the answers
• Anonymous
7 years ago

An operational amplifier is an electronic device that magnifies the voltage across two of its terminals. The equation for this device is:

Vout = A*(V+ - V-), where A is called the gain of the operational amplifier.

When you add other components around the operational amplifier, like resistors, you can use it to perform inversion or non-inversion. Also called an op-amp, this device is one of the primary circuit components used by all electrical engineers.

• Login to reply the answers
• Operational amplifier (OP – AMP) Linear built-in circuits are being used in a quantity of digital applications, similar to in the fields like communication, scientific electronics, instrumentation manipulate and so on. An foremost linear IC is an operational amplifier. OP-AMP is an effective state gadget equipped of sensing and amplifying dc and ac input indicators. OP-AMP is an amplifier with two inputs (differential inputs) and a single output. OP-AMP consists of 20 transistors, 11 resistors and one capacitor. It probably requires a confident and bad vigour provide (twin vigor deliver). This makes it possible for the output voltage to swing positive and terrible with recognize to floor The primary traits of OP-AMP are : (i) very excessive input impedance and even infinity which produces negligible present on the inputs, (ii) very excessive acquire, (iii) very low output impedance and even zero, so as to not have an impact on the output of the amplifier via loading. An OP-AMP is so named, due to the fact it was once at first designed to perform mathematical operations akin to addition, subtraction, multiplication, division, integration, differentiation and so on in analog pc. Nowdays OP-AMPs are utilized in analog pc operations and in timing circuits.

• Login to reply the answers
• Operational amplifier commonly referred as Op-amp, is a linear Integrated circuit (IC 741), which has a wide variety of application in audio communication, medical electronics, instrumentation control, etc.

Op-amp can perform many arithmetic operations like- addition, subtraction, multiplication, division, integration, differentiation etc and it can also amplify the voltage signal present at the input therefore it is called as Operational amplifier.

It has two input terminal and one output terminal, the input terminal with ‘+’sign is called non-inverting terminal and the input terminal with ‘-‘ sign is called inverting terminal. V+ and V- are two power supply terminals.V+ (pin 7) is connected to the positive terminal of one power supply source and V- (pin 4) is connected to the negative terminal of other power supply source. hence op-amp has five basic terminals, two input (2,3 pin), one output (6 pin), two power supply terminals(7,4 pin).The PIN diagram of 741 Op-amp IC is shown in figure-2. The Pin 1 and 5 are used for dc offset and pin 8 is not connected (NC).

https://www.electrikals.com/

• Login to reply the answers