![]() This can be extremely educational, if you're trying to build an ultra low noise low pass input then build a boring low pass input with a 741 to wrap your brain around the "low pass" part of the project, then figure out the modifications needed (if any.) to substitute in a low noise amp to divide and conqueror a two part project like that. So if you need higher freq or different voltage limitations given that the original design was very vanilla, substituting a somewhat different amp will almost certainly work. No one has mentioned the social signalling aspect in that a circuit using a 741 will probably work with most any opamp, at least for a relaxed definition of "work". I imagine maybe I've worked on a circuit with one on in that time but I genuinely can't recall it. In my experience, the 741 wasn't anyone's choice then or since - there were always much better and cheaper parts to use. I've been designing for 30 years, starting with mid-volume equipment in the mid-80s. In modern devices, many of these characteristics are negligible or practically non-existent. Few/no op-amps of 20 years past have brandished so many of these so prominently. It has the significantly-large input offset voltages and input currents, needs the offset null, shows the bandwidth/gain product so vividly. It's a good example for teaching students the characteristics to be concerned about, those weaknesses that highlight the inner workings of the op-amp. One of the reasons I think it persisted for so long beyond the mid-80s, when it was well superseded, was because of its many bad characteristics. It'd have passed into history, like the OC71 which was the BC108 of the mid/late 60s. If there weren't loads of textbooks dating back decades that used the 741 as an example, I'd be surprised if many people knew of it now. I've been an electronics designer since 1980 and I have never used or specified a 741 in any design I've been associated with.
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