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Why is the 741 op amp still produced?
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Zero999:

--- Quote from: coppice on September 23, 2020, 03:41:01 pm ---
--- Quote from: Zero999 on September 23, 2020, 12:49:13 pm ---What are you talking about? 5V is pretty standard from USB/wall wart power supplies. True, it's often regulated down to 3.3V or whatever, but it's still available at the input.

--- End quote ---
What are you talking about? Most of the world's electronics doesn't run from a USB wall wart. 15 years ago many people complained when you offered them a part that could only work from 3V. If you were in a silicon vendor the sales people were endlessly asking for 5V tolerant parts from the designers. That has changed. Get with the times. Automotive seems to be the last bastion of 5V, but that is changing.


--- Quote from: Zero999 on September 23, 2020, 12:49:13 pm ---Regarding automotive applications: that sounds like bad/lazy design to me. The LM321 can work from an unregulated power supply, so no it doesn't need to be regulated.  It just requires the usual anti-load dump transient protection, which you need anyway before the 5V/3V regulator. It can also tolerate its input voltages up to 32V, even when run from lower power supply voltages.

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Have you compared the price of an LM321 with an LMV321? Who wants to pay the price of a large geometry part that can tolerate high voltages, when most of your module is running from 3V or 5V anyway?

--- End quote ---
USB wall warts seem to be pretty universal.

The LM321 is cheaper than the LMV321. There clearly isn't any more debate to be had. If you've got 5V, or higher available, use that and the LM321, rather than 3V and the LMV321.
https://www.digikey.com/products/en/integrated-circuits-ics/linear-amplifiers-instrumentation-op-amps-buffer-amps/687?FV=-8%7C687&quantity=0&ColumnSort=1000011&page=1&k=LM321&pageSize=25&pkeyword=LM321
https://www.digikey.com/products/en/integrated-circuits-ics/linear-amplifiers-instrumentation-op-amps-buffer-amps/687?FV=-8%7C687&quantity=0&ColumnSort=1000011&page=1&k=LMV321&pageSize=25&pkeyword=LMV321
coppice:

--- Quote from: Zero999 on September 27, 2020, 10:33:03 am ---The LM321 is cheaper than the LMV321. There clearly isn't any more debate to be had. If you've got 5V, or higher available, use that and the LM321, rather than 3V and the LMV321.
https://www.digikey.com/products/en/integrated-circuits-ics/linear-amplifiers-instrumentation-op-amps-buffer-amps/687?FV=-8%7C687&quantity=0&ColumnSort=1000011&page=1&k=LM321&pageSize=25&pkeyword=LM321
https://www.digikey.com/products/en/integrated-circuits-ics/linear-amplifiers-instrumentation-op-amps-buffer-amps/687?FV=-8%7C687&quantity=0&ColumnSort=1000011&page=1&k=LMV321&pageSize=25&pkeyword=LMV321

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I find your use of Digikey as a measure of real prices hilarious.
Zero999:

--- Quote from: coppice on September 27, 2020, 10:42:27 am ---
--- Quote from: Zero999 on September 27, 2020, 10:33:03 am ---The LM321 is cheaper than the LMV321. There clearly isn't any more debate to be had. If you've got 5V, or higher available, use that and the LM321, rather than 3V and the LMV321.
https://www.digikey.com/products/en/integrated-circuits-ics/linear-amplifiers-instrumentation-op-amps-buffer-amps/687?FV=-8%7C687&quantity=0&ColumnSort=1000011&page=1&k=LM321&pageSize=25&pkeyword=LM321
https://www.digikey.com/products/en/integrated-circuits-ics/linear-amplifiers-instrumentation-op-amps-buffer-amps/687?FV=-8%7C687&quantity=0&ColumnSort=1000011&page=1&k=LMV321&pageSize=25&pkeyword=LMV321

--- End quote ---
I find your use of Digikey as a measure of real prices hilarious.

--- End quote ---
The LM321 is also cheaper than the LMV321 in Mouser and RS Components.
coppice:

--- Quote from: Zero999 on September 27, 2020, 11:41:16 am ---
--- Quote from: coppice on September 27, 2020, 10:42:27 am ---
--- Quote from: Zero999 on September 27, 2020, 10:33:03 am ---The LM321 is cheaper than the LMV321. There clearly isn't any more debate to be had. If you've got 5V, or higher available, use that and the LM321, rather than 3V and the LMV321.
https://www.digikey.com/products/en/integrated-circuits-ics/linear-amplifiers-instrumentation-op-amps-buffer-amps/687?FV=-8%7C687&quantity=0&ColumnSort=1000011&page=1&k=LM321&pageSize=25&pkeyword=LM321
https://www.digikey.com/products/en/integrated-circuits-ics/linear-amplifiers-instrumentation-op-amps-buffer-amps/687?FV=-8%7C687&quantity=0&ColumnSort=1000011&page=1&k=LMV321&pageSize=25&pkeyword=LMV321

--- End quote ---
I find your use of Digikey as a measure of real prices hilarious.

--- End quote ---
The LM321 is also cheaper than the LMV321 in Mouser and RS Components.

--- End quote ---
Your point is? These are all places that serve low volume customers where prices bear little relation to volume prices. One part may be only 2 times the volume price, while others can be 100 times the volume price. Not only do these places not give you a clue about volume prices, they don't even give you a clue about relative prices.
Kleinstein:
The LM321 are an odd product: quite a few of the LM321 versions seem to be actually LM358 dies using only one half: the supply current is usually the same as both OPs from the LM358 and not halve (or only slightly more)  :palm:. There seem to be a few now with lower current (e.g. from ONS).

For low voltage use (e.g. up to 5 V) there are quite a few affordable rail to rail CMOS OPs (e.g. MCP600x) - maybe not cheaper than the LM321, but below the 741.
One can also have a faster and less crossover distortion OP otherwise similar to the LM358 (e.g. MC33171-4) - this one could replace the 741 in most cases.
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