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Why is the 741 op amp still produced?
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David Hess:
It would sure be nice to have transistors arrays built on the modern 36 volt complementary bipolar process used for rail-to-rail precision parts, high slew rate voltage feedback operational parts, and current feedback operational amplifiers.  For a while after Linear Technology released resistor arrays based on their thin film resistor process, I hoped they would release transistor arrays but they never did, and they discontinued their LT1088 thermal RMS converter.

THAT Corporation sells matched quad transistor arrays in both polarities intended for audio applications which might have acceptable availability, but they are not cheap.

National used to make the LM389 which was an LM386 class audio amplifier plus three uncommitted NPN transistors which was a useful and inexpensive source for matched monolithic transistors.
EEVblog:
Simple, it's a known quantity and industry standard used by countless engineers for generations.
When you ask "why is it still used", think instead "what would replace it". Better yet, set up a poll and see what results you get, I guarantee there will not be a consensus on an answer.
That non-consensus is why the 741 is still the jellybean opamp choice.
floobydust:

--- Quote from: David Hess on September 20, 2020, 09:05:58 pm ---
--- Quote from: floobydust on September 19, 2020, 08:55:57 pm ---Why is a LM358 $0.15 but a better part over 10x the cost? Do they have more gold-pressed latinum inside?
An op-amp that has true competition has a reasonable price. Multiple-sourced 741, 358, 4558 is also why they are still alive.
--- End quote ---

The 358/324 were optimized from the start for small die size which is why dual and quad parts were even possible.  Improved replacements for them like the LT1013/LT1014 are optimized for performance and are huge in comparison.

--- End quote ---

I think the main driver is op-amp cost. They can be a huge hit to your BOM costs.

Linear Tech is top quality and extremely expensive.  LT317AT is USD$5.00 and LM317T-DG $0.77 that's a monster difference.
LT1013CN8  USD$5.75 16wk lead-time when it's out, I've had to wait that.
LM358PE4 $0.36 and never out of stock. I don't see the silicon area as the cost multiplier of 16x although I'm not an expert on the process and die sizes. Sure the LT1013 eliminated the PNP O/P tranny and added a bunch of others to crank up the gain. Kudos to LT for having the balls to update the old dog op-amps. I'd pay double or triple the price but no more.
David Hess:

--- Quote from: EEVblog on September 21, 2020, 04:37:33 am ---Simple, it's a known quantity and industry standard used by countless engineers for generations.
When you ask "why is it still used", think instead "what would replace it". Better yet, set up a poll and see what results you get, I guarantee there will not be a consensus on an answer.
That non-consensus is why the 741 is still the jellybean opamp choice.
--- End quote ---

The 741 also has better specifications than many similarly priced but modern parts, like its common mode rejection.


--- Quote from: floobydust on September 21, 2020, 05:36:39 am ---Sure the LT1013 eliminated the PNP O/P tranny and added a bunch of others to crank up the gain. Kudos to LT for having the balls to update the old dog op-amps. I'd pay double or triple the price but no more.
--- End quote ---

The LT1013 is second sourced from TI so has reached a reasonable price.

In production quantities, real precision parts like the LT1097 are a deal.
SeanB:
Biggest user is Aerospace, simply because the darn things are rugged, reasonably reliable, are available in rad hard versions, and also are the part that is certified for this application.  gotten them and abused them, and they are rugged, even when using them with 44 volt power rails, so they would be able to output 30V peak to peak, replacing some dead OP20 amplifiers, though i did add the TO100 heatsinks to them to keep them cool, unlike the OP20's, which had cooked nicely.

Yes for general purpose use at lower voltages there are better parts, but for industrial logic with not much required frequency wise, and with a truly big common mode range hard to beat, plus they will survive transients that would kill other opamps, simply because the die is so large.
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