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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.
Wiki User
∙ 14y ago
Wiki User
∙ 14y agoInput Impedance of ideal Voltage opamp is Infinite
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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 does 10 megohm input impedance mean?
10 megohms is the resistance through which 10 volts would push 10 microamps of current. Input impedance is the resistance seen by a signal source when connected to the input Often, this means there is a 10 megohm resistor in series with the input going to a virtual ground on an opamp circuit. 10 megohms is a common input impedance for a digital voltmeter.
What is a difference between an operational amplifier and instrumentation amplifier and can you use one opamp to perform a same task as 3 opamp instrumentation amplifier?
An op amp is made from transistors, resistors and capacitors. It is enclosed in a "chip". A basic instrumentation amp is made of 2 op-amps. you can't have a single op-amp perform as good as a instrumentation amp, although it can perfrom the same task. An i-amp has much better CMMR (common-mode rejection) and a higher input impedance.
What are the three factors that effect the electrical parameters of a op-amp?
Supply voltage , temperature , frequency are factors that effect the electrical parameters of opamp
What isDifference between ordinary rectifier and precision rectifier?
A simple rectifier circuit uses a diode and there is a turn ON voltage for the diode. The input voltage has to exceed the turn ON voltage (0.6V for ordinary Si diode) before rectification is achieved. A precision rectifier is an active circuit using an opamp and a diode in the feedback loop. This overcomes the turn-on "knee" voltage. The op amp reduces the turn-on voltage of a diode in its feedback loop by a factor equal to the open-loop gain of the op amp. For practical op amp gains this reduces the forward voltage to a fraction of a mV, thus giving a "precision" or near ideal diode characteristic for the rectifier function.
What is the applications opamp buffer circuit?
An opamp buffer circuit is one where the input signal is connected to the plus input, and the output is connected to the minus input. Within the performance limitations of the opamp, the output will track the input. The advantage of the buffer circuit is that is presents very little load impedance to the input signal, while providing a low impedance from the output to drive whatever circuitry is connected there.
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.
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 voltage gain is high in op amp?
A practical opamp is designed to approach the characteristics of the ideal opamp as closely as possible. The open loop voltage gain of an ideal opamp is infinite, so while this is actually impossible to achieve practical opamps are built with as high an open loop voltage gain as possible.
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.
Why emitter follower is used in circuits?
The (Class C, Common Collector) Emitter Follower is used to amplify the available current from a voltage driving circuit that might be disturbed by the load impedance. If the actual voltage value is important, the emitter follower is often teamed up with an opamp which sets the emitter voltage based on the input voltage.
What does 10 megohm input impedance mean?
10 megohms is the resistance through which 10 volts would push 10 microamps of current. Input impedance is the resistance seen by a signal source when connected to the input Often, this means there is a 10 megohm resistor in series with the input going to a virtual ground on an opamp circuit. 10 megohms is a common input impedance for a digital voltmeter.
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.
Give the definition of output offset voltage of Op-Amp?
The output voltage of a opamp when the input of inverting and non inverting terminals are grounded
What are characteristics of an ideal diode?
An ideal diode:Passes current in one direction only. (Under forward bias).Has no leakage current (passes no current under reverse bias).Has no forward voltage drop. (No voltage loss under forward bias - a real diode has Vd~=0.7)See links for more details.
What is the difference between Real and Ideal values?
Real culture is defined as what people actually do, whereas ideal culture is what people say they do. For example, tribal hunters may say that they are going to bring back monkey meat for the evening meal, but they may not succeed. Americans may tell others that they stop at eight sided traffic signs, but how often do they actually do it?
What is the use of offset null in an opamp?
A: Any offset whether is voltage or current is an output error to contend with.
