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A comment on ZRNA – Software-defined analog circuits. Parent comment

Re:ZRNA – Software-defined analog circuits by theon144 on Thursday August 01, 2019 @04:22AM (#20582052)
>The unity gain is 18Mhz which wouldn't be able to even keep up with a modern AVR clock(16-20Mhz).

I am not sure what this implies; would you be able to build an equivalent, digital circuit (with presumably a ADC and a DAC stage) with an average AVR then? Or what's the clock comparison for?

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Re:ZRNA – Software-defined analog circuits by raverbashing on Thursday August 01, 2019 @07:57AM (#20582996)
The unit gain (for an OpAmp at least) is related to the bandwidth, the gain decreases linearly (in the dB scale) as the frequency goes up.

You want to be looking at the -3dB range to know +/- the actual useful bandwidth

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Re:ZRNA – Software-defined analog circuits by theon144 on Thursday August 01, 2019 @10:45AM (#20584133)
Okay, but I'm still confused as to why would you compare it to AVR frequency; was that just a random comparison ("this car goes so slow you could outrun it") or would the frequency of a MCU clock being higher than the bandwidth of an op amp ever be important?
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Re:ZRNA – Software-defined analog circuits by raverbashing on Thursday August 01, 2019 @11:07AM (#20584409)
Correct, the comparison makes no sense

> would the frequency of a MCU clock being higher than the bandwidth of an op amp ever be important

Unless you specifically want to capture the analog waveform of the clock signal of that processor, it is unimportant

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