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Impedance is the total opposition to current flow. It includes both resistance AND reactance (capacitive and inductive). Impedance varies with frequency, while plain resistance does not.
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Wiki User
∙ 14y ago
Wiki User
∙ 13y agoThe input impedance of a circuit is the total impedance as seen by the source. For example, if a voltage source is connected to one end of a two resistor divider network, where the other resistor is connected to source ground; and each resistor = 1K ohms, then the input impedance is the total impedance seen by the source = 2K ohms.
The output impedance of the circuit is determined by finding the resistance obtained by looking into the output terminal of the input circuit which is exactly the same as the thevenin resistance of the circuit.
Thus, the output impedance of the circuit will be Rout = R1 R2 = 0.5KΩ
Wiki User
∙ 14y ago- Symbol Z) A measure of the total opposition to current flow in an alternating current circuit, made up of two components, ohmic resistance and reactance, and usually represented in complex notation as Z = R + iX, where R is the ohmic resistance and X is the reactance.
- An analogous measure of resistance to an alternating effect, as the resistance to vibration of the medium in sound transmission
Wiki User
∙ 13y agoImpedance is the total opposition to current in an AC circuit. It is the vectorial total of resistance, capacitive reactance, and inductive reactance.
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What was the effect on the input impedance of lowering the operating frequency?
The input impedance should increase slightly for the lower frequency, when using a capacitive circuit.
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.
How you can eliminate loading effect in amplifiers?
By increasing the input impedance of amplifier.
Which is better high input impedance or low input impedance and why?
That depends on the output impedance. In electronic we use 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.
Compared to bipolars FETs have-a high input impedance b low input impedance c same input impedance?
FET s have very high input impedance when compared with Bipolar transistors.
Why a high input impedance?
A circuit (an amplifier) typically has a high input impedance so that it does not unduly load the input circuit. Any such load could cause distortion, and that is generally not desired.
What are the applications of fixed bias circuit?
low input impedance
What was the effect on the input impedance of lowering the operating frequency?
The input impedance should increase slightly for the lower frequency, when using a capacitive circuit.
What are the applications of fixed bias amplifier circuit?
low input impedance
What are the Advantage of mosfet over fet?
MOSFET has high input impedance and offer input signal isolation from the circuit
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.
How you can eliminate loading effect in amplifiers?
By increasing the input impedance of amplifier.
Which is better high input impedance or low input impedance and why?
That depends on the output impedance. In electronic we use 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 advantages when using a digital voltmeter?
The electronic voltmeter has higher input impedance than other voltmeters, such as traditional VOM's. As a result, it loads the circuit under test to a smaller extent, introducing a smaller error in measurement. Many electronic (or digital) voltmeters have an 11 Megohm or 20 Megohm input impedance, as opposed to a typical 20 Kiloohm per volt impedance of a typical VOM with a 50 microampere movement. Some high end electronic voltmeters have an input impedance well into the thousands or millions of Megohms.
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.
Compared to bipolars FETs have-a high input impedance b low input impedance c same input impedance?
FET s have very high input impedance when compared with Bipolar transistors.
What is need of voltage follower circuit?
It's a buffer circuit - it provides a high impedance input, and low impedance output with ~ unity gain. If you have a circuit that cannot drive much power, you can use a voltage follower to help. Also, if the input or output of a circuit needs to stay a specific value, such as with filters, you can easily control this due to the isolation the voltage follower provides.
