All Questions
Tagged with input-impedance noise
5 questions
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Impedance of antenna and noise propagation
I would like to better understand how noise is radiated.
Suppose the circuit under study is a circuit with a DC/DC converter (source of noise) and an analog circuit (receiver) which is very sensible ...
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Can you reduce audio noise by decreasing input impedance with a resistive load?
First asked this over at sound stackexchange but they pointed me over here as a better place for it.
A general question but inspired by a specific example so framed as such.
I have powered studio ...
- 131
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Why is the input noise of an op-amp often lower than the Johnson noise equivalent to its input impedance?
As an example, the OPA227 has 3.5nV/sqrt(Hz) input voltage noise density (at 10Hz). Its input impedance is 10MΩ, which has an equivalent Johnson noise of 1μV/sqrt(Hz) at room temperature - much larger ...
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How to set Rin & Rfb to optimize input impedance / Johnson noise of an opamp circuit?
This question follows great answers I got for my previous question about GBW. It teaches me I should use two stages in my microphone preamp project. This leads me to this question:
Considering the ...
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How to avoid Johnson noise in high input impedance amplifier
I don't have a circuit I'm working on, this is more of a theoretical question - I am trying to remedy a flaw in my understanding.
Imagine I want to build a high input impedance amplifier to work in ...
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