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7 votes

Which noise sources dominate in a receiver?

It's a compromise. You can easily make thermal noise dominate by adding an LNA stage with enough gain that the thermal noise exceeds the quantisation noise. Then strong signals will exceed the ADC's ...
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6 votes

What is the tradeoff in decreasing the frequency bandwidth when reducing noise of a resistor?

It depends on your application. You need to provide the bandwidth that your application requires. If you reduce the bandwidth below that value, you will reduce the resistor noise at the expense of ...
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4 votes

PWM LED strip dimmer induces noise in power supply

PWM-ing the output of a switched mode power supply (SMPS) is nothing different than testing its transient response (e.g. 0-to-100% then 100%-to-0), but way faster. Load transients are normally ...
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3 votes

PWM LED strip dimmer induces noise in power supply

If you have lots of LEDs (100W is a lot), you can reduce the current ripple with multichannel. Instead of using just two MOSFETs, you can use as many as you have PWM channels on the ESP32 (so, 8 or ...
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3 votes
Accepted

What is the core material being used in CMC (Common mode choke) and DMC (Differential mode choke)?

Depends on the working frequency range, of course. But for almost all applications, MnZn (Manganese Zinc) ferrites are used. Sometimes symbols look confusing, yes. If you see a single inductor with ...
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3 votes

What is the tradeoff in decreasing the frequency bandwidth when reducing noise of a resistor?

It all depends on the application. If you're building an audio amplifier and want to minimize thermal noise, you can decrease the bandwidth of your amplifier. The tradeoff of course is that you can'...
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2 votes

Noise of low-frequency RC high pass filter preamplifier circuit with LT1028

Adding the specifications cleared things up greatly. You have parameters that are at odds with each other which is expected. I ran a few different runs using the .step statement with different input ...
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  • 3,780
2 votes

What is the tradeoff in decreasing the frequency bandwidth when reducing noise of a resistor?

Halving bandwidth is the same as taking two measurements and averaging them together. The trade off is that it takes twice as long and you'll potentially average away any rapidly changing component ...
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  • 10.4k
2 votes

What is the core material being used in CMC (Common mode choke) and DMC (Differential mode choke)?

In the old days, transformers were just made with two materials for the core - air, and some type of magnetic material, iron being the most common back then. So an air core transformer just used the ...
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  • 7,169
2 votes

PWM LED strip dimmer induces noise in power supply

Rather than fixed with PWM, it ought to be a variable f that increase due to hysteretic feedback % with series L. Your low PWM rate must be stimulating a resonant pole in the regulator with sub-...
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2 votes

Which noise sources dominate in a receiver?

Thermal noise tends to dominate in an RF receiver. The bit-depth can be large enough so that the corresponding quantization noise becomes less significant w.r.t thermal noise. Quantization noise can ...
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1 vote

How to reduce or eliminate inductor sound noise in a buck SMPS?

The HT7A6322 has a fixed 60KHz oscillator - it shouldn't change depending on load. I think the problem is that your load is very light. It is drawing almost no current, causing the regulator to go ...
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1 vote
Accepted

Overall CMRR of analog front-end

CMRR means that a tiny part of the input common mode voltage will be converted to the differential mode signal output. Therefore, subsequent stages cannot remove this common-mode-error anymore, ...
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1 vote
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Waveform acquired from scope, what is the sample rate for post processing?

You will always get a buffer of 2500 samples, but the sampling rate used depends on the timebase used. The exact sampling rate values for timebases are listed in the manual.
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1 vote

Which noise sources dominate in a receiver?

I appreciate the other answers given, but I'm adding this answer to my own question because I think I found a more detailed answer here. According to the author, it is typical to design for thermal ...
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  • 151
1 vote

What is the core material being used in CMC (Common mode choke) and DMC (Differential mode choke)?

Material is as others have answered; as for construction, CMCs optimize maximum inductance at low current (since the common mode is supposed to be isolated, or "current compensated" as they'...
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  • 1,035
1 vote
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Power supply noise reduction

To understand any filter design you need to have expectations of what is signal, noise, SNR, voltage, current, and Impedance in terms of amplitude and f. Then we can ask some better questions. But ...
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1 vote

How to avoid noise on serial connection?

I've seen this kind of issue when you get ground noise between the boards (Jetson and motor drive). Make sure the ground current for the motor does not flow on the ground line between the jetson and ...
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