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What is the input impedance of an ideal voltage op-amp?
To get all the voltage from a source to a target without loss you need voltage bridging, that is a relative low output impedance to a higher input impedance. Usualy the input impedance is more than ten times higher then the output impedance.An input impedance is called also a load impedance or an external impedance.An output impedance is called also a source impedance or an internal impedance.
Why input resistance of voltage amplifier is infinity?
For the successful amplification of the input signal the opamp should have ideally infinite input impedance . It should act like a buffer amplifierBUFFER amplifier--------------------->1.input impedance infinity2.output impedance zerothe reason is thatAny signal source will have source impedancefor the signal not to get lost and dropped across source impedance we ideally insert infinite impedance in series with it which makes the whole drop across the infinite impedance but not across the sourcesimilarly at the output zero impedance is used where in no part of the signal should be left behind in the op amp as a drop
What is loading effect of op amp?
An 'ideal' op-amp has infinite input impedance, and real ones that you can buy for anickel come pretty close. That means that the input impedance or "loading effect" ofan op-amp all by itself is nearly zero, and the loading effect of a circuit that youbuild with an op-amp is completely determined by the components you choose toconnect to it. You design the circuit to load the previous stage in any way you want.
If two output tubes are run in parallel and the primary impedance of the audio transformer is cut in half will a single-ended amp yield twice the output?
Yes it can if it's connected in a push pull reconfiguration
Why should the input resistance of a instrumentation amplifier be as high as possible?
Input resistance answerRequired because sensors typically have a high or unbalanced source impedance. It is ideal to have no current flow through and OP amp therefore ideal to have infinite input impedance. If current is flowing through this could cause an error in the output. Please comment on this, not sure if correct.Comment: If you are not sure about your facts, I see little point in offering an answer.AnswerConnecting an amplifier to a transducer/sensor inevitably changes the conditions of the phenomena being measured. This is due, primarily, to the amplifier drawing, an albeit small, current from the transducer. The higher the amplfier's input impedance, the lower the current drawn, and hence the less the disturbance to the original conditions.
Why output impedence is high in opamp?
Output impedance in an op-amp is not high - it is low - input impendance is high, and this is because the input stage transistors have high gain.
What is the input impedance of an ideal voltage op-amp?
To get all the voltage from a source to a target without loss you need voltage bridging, that is a relative low output impedance to a higher input impedance. Usualy the input impedance is more than ten times higher then the output impedance.An input impedance is called also a load impedance or an external impedance.An output impedance is called also a source impedance or an internal impedance.
What are the dc characteristics of an OP-AMP IC 741?
High gain high input impedance low output impedance
Why input resistance of voltage amplifier is infinity?
For the successful amplification of the input signal the opamp should have ideally infinite input impedance . It should act like a buffer amplifierBUFFER amplifier--------------------->1.input impedance infinity2.output impedance zerothe reason is thatAny signal source will have source impedancefor the signal not to get lost and dropped across source impedance we ideally insert infinite impedance in series with it which makes the whole drop across the infinite impedance but not across the sourcesimilarly at the output zero impedance is used where in no part of the signal should be left behind in the op amp as a drop
Why input impedance of operational amplifier is infinite?
Input impedance (Zin) is assumed to be infinite to prevent any current flowing from the source supply into the amplifiers input circuitry. Infinite Input impedance is one of the Ideal Characteristics of the Op-Amp. With an assumption of Infinite Input impedance, there is no Loading on the preceeding stage to the Op-Amp (i.e. Supply.) or The Op-Amp under test does not draw any current from the I/p Supply to it's internal Circuitry.
What is a voltage follower Op-amp?
It is an amplifier that has no gain or a gain of one mainly used for isolation .
Why the input resistance of opamp is high?
Because op amp consist differential amplifier and they posses high input impedance so that op-amp also posses high input impedance.
What are the properties of an op-amp?
Properties of an op-amp are as follows: 1.Very high open loop gain which remains constant over the frequency range in which the device is to be used. 2.Very high input impedance to minimize the current drawn by the circuit with little losses. 3.Very low output impedance 4. They are stable, i.e. not liable to burst into parasitic oscillation. 5. They are free from drift caused by ambient temperature changes.
Which input terminal of op-amp has high impedance?
both are considered to be hi impedance inputs. If a sensor requires a high impedance in order to maintain accuracy, we usually connect that sensor to the positive (+) input terminal of the op-amp.
Conditions for faithful amplification?
1. Signal to noise ratio should be low at the amplifier outlet. (Vaccuum tube amps are best.) 2. No distortion at the output due to the amp being overdriven. 3. Impedence matching at the input and output.
Which characteristics of Op-Amp is responsible for virtual ground?
The main parameter responsible for virtual ground of an Op-Amp is Input Impedance . Generally , for an Op-Amp it is very high . So , we can conclude that the characteristics of an Op-Amp responsible for virtual ground is high input impedance .
What are practical applications of a transformer coupled amplifier?
Well the purpose of the transformer in an amplifier is impedance matching. Lets say the transformer is on the input of a audio amp. Now the amp circuitry has an input impedance (this is important because matching the impedance gives us maximum power transferred from the input signal source to the amp circuit, and that increases performance) and a microphone has an output impedance. So if the microphone is 10,000 ohms and the amp circuit is 500 ohms then the transformer is designed to transform 10,000 ohms to 500 ohms for better signal transfer. If the trans former is on the output of an amplifier the trans former transforms the output impedance of the of the power amp circuit to the input impedance of the load. If the output is a speaker (usually 8 ohms ) and the output impedance of the amp circuit is 1000 ohms then for maximum power transfer the transformer trans forms 1000 ohms to 8 ohms. This was the case using electron tubes. Now with transistors, amplifier circuits can be built with lower output impedances (common collector circuit in a class B power amp) so the costly transformer can be eliminated. Also Audio transformers are made slightly different in design than power transformers. Ausio transformers are designed with higher resistance in the windings to enable a wider frequency response where as power transformers are designed with much lower resistance to keep heating minimized while passing only one power frequency (60 hertz) at large amounts of power. Roger nsc@psu.edu
