Re:How to Set Up an OpAmp Circuit to Do Complex Mathematics
by brandmeyer on Monday February 20, 2017 @11:02PM
(#13693194)
Like anything, its a cost tradeoff. DSP can be much cheaper than active analog for many frequency ranges. You can certainly oversample your way to a cheaper antialiasing filter in many applications. But you can't ever eliminate it entirely.
3 Gigasamples / second: http://www.ti.com/lit/ds/symlink/adc07d1520.pdf
The fastest OpAmp I can find is this 18GHz GBP: http://www.ti.com/lit/ds/symlink/ths4303.pdf
At 3 GHz, the OpAmp would only offer a gain of 6 which isn't really enough for much accuracy.
Granted, the OpAmp is like $5 and the ADC is hundreds of dollars (and the ADC is only 7-bit accurate)... but the digital world has gotten scary fast and scary good.
That's why Oscilloscopes, even GHz-Oscilloscopes are being made with digital technology today.
Hell, this crazy product raises eyebrows: http://www.digikey.com/product-detail/en/analog-devices-inc/...
26Giga-samples (Nyquist of 13). I mean, 3-bits sucks, but holy crap is that fast. A 26GHz ADC would be able to perform digital-filter analysis on 2.4GHz Bluetooth and Wifi without any aliasing what-so-ever.