4 ms·
Fire control computers, like on a navy ship, were faster than digital computers of the day. YouTube has a number of videos on them. An opamp performs multiplic
by WorkerBee28474 4y ago
Fire control computers, like on a navy ship, were faster than digital computers of the day. YouTube has a number of videos on them.
An opamp performs multiplication faster than a digital computer (speed of light vs a few cycles). It's not super useful on its own, but it does fit the criteria.
In Veritasium's video 2/2 on analog computers [0] they show some startup products near the end.
[0]https://youtu.be/GVsUOuSjvcg?t=898 https://youtu.be/GVsUOuSjvcg?t=898
- gaze 4y agoWhat no. Opamps don’t multiply and they don’t operate at the speed of light. They have some timescale that goes like their bandwidth, which depends on their feedback path.
- Animats 4y agoYes, feedback op-amps definitely have bandwidth limits. Although you can get ones in the gigahertz range now. Analog multiplier ICs are available.[1] They're not common, and they cost $10-$20 each. Error is about 2% worst case for that one. There are several clever tricks used to multiply. See "Gilbert Cell" and "quarter square multiplier". [1] https://www.digikey.com/en/htmldatasheets/production/1031484/0/0/1/ad633.html https://www.digikey.com/en/htmldatasheets/production/1031484...
- boltzmann-brain 4y agoThe propagation time around the feedback loop is still (length of loop) / (speed of light*slowdown constant), so yes, "at the speed of light".
- osamagirl69 4y agoThis is absolutely not true, the speed of analog circuits is (by a significant margin) determined by parasitic capacitance, inductance, and resistance of the components. To put numbers to it, a typical high performance analog multiplier might have a loop length of 1cm for the feedback path. This circuit should theoretically operate at 30GHz, but realistically such circuits operate with a bandwidth measured in megahertz.