Questions tagged [impedance]
Impedance defines the voltage/current characteristic of any dipole circuit.
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Infinite output impedance in amplifier, instead of 0?
The question asks: "Exercise 14.5 Assume an ideal op amp and use the summing-point constraint to find an expression for the output current io in the circuit of Figure 14.14. Also find the input ...
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Why does tan (θ) equals -j in impedance of reactive circuits?
I'm having trouble understanding the maths for impedance.
Suppose we have a voltage of \$V(t)=V_{0}sin({\omega}t)\$ and we plug this into the capacitor equation \$I(t)=C\frac{dV(t)}{dt}\$. This would ...
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Do audio impedance mismatches cause reflection (ie, 8-Ohm output to 20kOhm input) ? Does it matter?
I understand that audio source⇒input impedance mismatches are normal, and this answer provides a good reason as to why. However, having worked with RF more than audio, mismatches cause reflection that ...
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What does impedance seen from input/output mean?
I am seeing it usually like impedance seen from input/output when we need to match impedances between two circuits. What does it even mean? Does impedance change based on where do you look from?
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Impedance measurement using AD 5933
I hope this message finds you well.
I am using the AD 5933 evaluation board for impedance measurement, The data sheet says it can measure the impedance up to 10M ohm. I am currently measuring the ...
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Source impedance-trace impedance - load termination impedance confusion
I drew an experiment PCB to better understand the PCB impedance. And when I look at the impedance at 1 GHz, it can be seen that it is 119 Ω at most points of the trace. Then, I created a source that ...
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Why does the voltage double at the end of line in a open transmission line (physical explanation)
I'm seaching a way to explain physically what happens in a wave reflection in a transmission line, if we apply a DC voltage in a open circuit transmission line, the voltage at the doubled.
I saw this ...
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Pi-Filter Simulations Comparison
I am trying to simulate the filter impedances on LTspice. There are two images of the simulation results of the same pi-filter on LTspice and Redexpert. Although I am not sure the parameters are ...
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How can this Clapp JFET oscillate when its gate is tied to ground at the resonance frequency?
How does the circuit below oscillate? It seems to have |gain| < 1 at its oscillation frequency of 2.25 MHz, yet it oscillates there.
My analysis:
The DC path is through L4 only, allowing a bias ...
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Non buffered CMOS logic gates working under load when using real components (LTSpice Sim)?
I'm experimenting with CMOS logic gates and have encountered something I am having a hard time understanding.
When I make an inverter using ideal components and measure the output, it works exactly as ...
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Is a smoothing capacitor only useful when the trace has impedance
Under conditions where maybe a capacitor is used maybe when perhaps there's a high impedance power supply and the source would cause current surges, maybe a subwoofer to a car battery that can't deal ...
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How can these passive RLC circuits change a sinusoid's frequency?
Given a sinusoid input of frequency f, an RLC network, no matter how complex, should produce a sinusoidal output of frequency f, with possible attenuation and phase shift. At least that's my ...
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What requirements of a feedback network are needed to produce oscillation?
I'm trying to understand how to analyze simple oscillators, and would like to know if my conclusions about the required feedback network are correct:
The simplest way to build an oscillator is with:
...
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How to analyze and simplify a voltage divider with a second voltage source?
How do I simplify the circuit below?
simulate this circuit – Schematic created using CircuitLab
I know that R2 and R3 form a voltage divider, but I can't figure out the input impedance that In ...
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Impedance for a guitar pedal into an Electrosmith Daisy Seed ADC
I'd like to be sure I can feed my guitar pedal signal into my Daisy Seed ADC to then work on it with digital signal processing algorithms.
Here is what I know about my problem:
It seems guitar pedals ...
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