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Comment by raverbashing | Hacker News Reader

Funny, I have actually used this one, the 4 means 4 OPAMPs in a single chip. IIRC there's also the TL082 with 2 OPAMPs.

Much more performant than the 741 (might have to do with 2 things: the 741 came early and was one of the pioneers and it is BJT only)

It's also curious how the the big butterfly transistors are at the input, components with a big die size are usually big for a reason (usually power).

One extra fact, the compensation capacitors are more like a wrench on gears and actually make the circuit "worse" (it lowers the overall bandwidth). But it is needed for stability purposes because good amplifiers will have a tendency to oscillate by themselves.

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> usually power

That may be true but I'm not sure it applies in this context. Another valid reason is because at a larger scale it is easier to get the dimensions to be within a fairly close tolerance of the counterpart and hence to get two parts that function well in tandem.

Matched pairs and current mirrors are exactly the right situations for this and so they tend to be oversized, even if that slows the parts down considerably.

Also, the input stage is where noise figure is critical. Larger transistors are lower noise figure.

If you build ~1MHz circuits with 741s and replace them with 071s, you'll notice how ass the 741s are.

Also, I've seen some people use 071s' inputs with no DC path to ground, and see their output slowly drift up/down because of tiny bias currents. Doesn't happen with 741s, usually.

That’s just crappy circuit design if they do that.

Is there a general purpose op amp that is the modern equivalent of the 741? Something with a much more recent design with widespread use.

What's wrong with the 741?

The 071 is also "jellybean" enough; both are still currently used in modern designs because how dirt cheap they are.

But they are "high voltage", non rail-to-rail anything, so people tend to use more modern options for new designs.

741 problems: terrible bias current, offset, input range, output range, power consumption, voltage requirements, GBW, noise.

They’re just horrid. Fine for noddy stuff like power supplies and PID loops etc though.

I don't have any particular problem with it. I majored in EE about 15 years ago, and haven't really looked at op amps since studying the 741. Just curious what's popular these days.

Also, there ARE objectively shit op amps that are old and crusty that pretty much nobody uses. I think it was the LM358 that basically had a broken output stage (class-B) that causes horrible output crossover distortion when you transition from sourcing to sinking current or vice versa.

http://www.ti.com/lit/ds/symlink/lm158-n.pdf

Page 13, Figure 16.

Q12 is a common emitter amplifier with an active load, that feeds directly into a class B output stage (pullup is a darlington with Q5 and Q6, and pulldown is Q13, with Q7 being a current limiter). I've never used this personally (for good reason) but I remember my mentors telling me this causes horrible CO distortion.

I doubt there is anything recent as iconic. Overall I think we have moved way beyond having individual generic iconic models at all. Digikey has like thousands (hundreds if you are old-fashioned and want through-hole) of different opamps which probably are mostly interchangeable 741 for most purposes, just pick any one of them.

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