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How to identify filter behaviour without memorizing different topologies

Look at the extremes. DC and very high frequencies. For DC you can remove the capacitors and short the inductors. For high frequencies you can short the capacitors and remove the inductors. By looking ...
• 7,955

How to calculate values for decoupling capacitors

Basically you want something close enough to the pin that at the edge rates in play the bounce is not too bad, and then something further away with (possibly) enough ESR to damp everything to keep the ...
• 16.1k
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Why is the output of a high-pass filter not 0 when the input is 0?

This could arise as the sum of the input offset voltages ... but for 3 opamps, that would only come to 3.9mV worst case, so that isn't it, especially since it's unlikely that the SPICE model has the ...
• 65.8k
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Design constraints when dealing with very high resistances in op amp's feedback loop

I used to do condenser microphone stuff professionally, which was very much this kind of thing (10G ohms with maybe a 30pF source). Cleanliness is VITAL, a bit of skin oil in the wrong place and you ...
• 16.1k
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What is the purpose of the 250uF capacitor in the LM386 circuit?

Yes, 470uF will work fine, it will just extend the bass response somewhat. It's a coupling capacitor (or a blocking capacitor, to block DC, if you prefer). The 10R + 50nF is a "Zobel Network", ...
• 327k

Conundrum: High pass filter passes DC?

The resolution to the conundrum is that there really is no conundrum. Your input, a step function, has infinite dc component (its Laplace Transform, $1/s$, goes to infinity as $s\rightarrow 0$). ...
• 2,487

• 4,978

Conundrum: High pass filter passes DC?

The circuit you are describing and the output is shown below. Let me know if I got it correct. There is no conundrum here. The HPF (capacitor) allows high frequencies to pass. The step voltage has a ...
• 5,743

How can I find the cutoff-frequency in real experiment?

It seems to be your task to figure out how to do this, and we don't solve homework for people. But your actual question here seems to be: I don't understand why I should find the method to determine ...
• 12.7k