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I'm trying to find a "same or better" equivalent replacement for the 747 opamp. The footprint / pinout can be different, I don't mind.

Using the parametric search on Arrow, while reading the datasheet for the 747 I found that an LT1355 might do as a replacement. However, they are quite expensive; $16.89 for one single IC (DIP package). Searching for LT1355 on Octopart shows that Arrow are the cheapest for this one, but the price is too steep for me. I'm fine around $8/pc.

What other dual opamps can serve as a replacement for 747?

bos
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    I can’t think of an opamp that is generally worse than a 741. Cruel, I know. – Andy aka Jan 20 '18 at 16:22
  • AW poor little 741s @Andyaka :) We had to start somewhere. – Trevor_G Jan 20 '18 at 16:27
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    @Andyaka How about the LM709, the 741's predecessor? Still there was a day when a 741 was "state of the art". We have just moved on. – Bimpelrekkie Jan 20 '18 at 16:31
  • Nowadays, the "jellybean" opamp is the LM324. – Olin Lathrop Jan 20 '18 at 16:55
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    OK I've been provoked LOL: [Reasons not to use a 741](https://electronics.stackexchange.com/questions/304521/reasons-not-to-use-a-741-op-amp/304522#304522) – Andy aka Jan 20 '18 at 16:57
  • [The 1458](https://www.intersil.com/content/dam/Intersil/documents/ca14/ca1458-1558-741-741c-lm1458-lm741-lm741c.pdf) is generally referred to as a "dual 741." So, if you need a part twice as bad as the 741, then you can get a 1458. The 1458 doesn't have the offset null pins, however. – JRE Jan 20 '18 at 17:56
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    LOL @Andyaka not saying you are not right, just not nice to make fun of the old... (says the old guy) – Trevor_G Jan 20 '18 at 18:09
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    @Trevor_G I'll be 60 this year but the only time I've ever touched a 741 is to desolder several from an old geetar amp in the 80s and replace 'em with what was better at the time, probably an OP-07 type device. I figured that because they actually had a noise spec listed they were quieter (and they were noticeably so). Never designed one. [op-amp history lesson](https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=4&ved=0ahUKEwiW1d7XkufYAhVEC8AKHXsCCBIQFgg6MAM&url=https%3A%2F%2Fwww.calvin.edu%2F~pribeiro%2Fcourses%2Fengr332%2FHandouts%2Fho18opamp.pdf&usg=AOvVaw34sd5IoWUfQQj2fOQyFzxB) – Andy aka Jan 20 '18 at 18:16
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    @Andyaka I just had my 60th.. still have the hangover. Yup never designed with one either. Used a couple in a kit when I was a lad though. They ARE good for one thing though. Teaching noobs why it is important to look for parts that have the requirements they really need... – Trevor_G Jan 20 '18 at 18:20
  • I'm fond of the TL062 (but NOT the T.I. parts). Lower Ib, lower power consumption, cheap. – Robert Endl Jan 20 '18 at 19:10

4 Answers4

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Usually asking for products/parts is off-topic but since this can benefit anyone who wants something better than a 741, I'm making an exception.

There are literally hundreds of suitable 741 replacement opamps.

The parts you list are waaaay too expensive. They likely have some special properties only few designs would need.

You should not be looking for a 741 replacement per sé but more a "generic opamp".

There are very usable opamps to be had for much less money. Like LM358, 10 for 1 Euro (shipping included!) on Ebay

other examples: MCP602, CA3140, TLC271

Most of these have versions with 1, 2 or 4 opamps in one housing.

You will have to compare the datasheets to see what suits your needs. Do pay attention to the supply voltage for these opamps as those can vary.

Bimpelrekkie
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  • Good information relevant to pricing here: https://electronics.stackexchange.com/questions/128699/why-are-max-ad-lt-parts-among-others-so-expensive – vofa Jan 20 '18 at 17:19
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If your looking for a very quite op-amp for audio then I would choose the TL071/TL072/TL074 series. They have the same pin-outs as the 741/RC4558, with the TL074 being a quad package.

They cost about $1 USD each, less in quantities. They are good enough for 16 bit audio, but not 24 bit or 32 bit audio. Those type of op-amps are expensive.

The TL071/TL072/TL074 series are JFET op-amps with high-impedance inputs so they do not load down their source, and you can use gain and offset resistors in the meg-ohms if you have to. The outputs can source or sink about 5 mA.

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The RC4558 is essentially a dual 741 (sans Vos adjust pins) in a DIP-8, SOIC-8 or TSSOP-8 package and was (and still is in some circles, at least the 'JRC' version) popular for audio work. It does not have huge crossover distortion of the cheaper LM358. There is a bit of crosstalk between the two halves that you may have to consider in some applications.

About 10 cents in 1K, Digikey lists one version of them at 35 cents in singles.

For many 741 applications you can use the LM324 (quad) / LM358 (dual). They are very cheap, and the input common mode range includes the negative rail, and the output swings near the negative rail. A pullup to +V can help mitigate the crossover distortion. Generally in the same class as the 741. For precision the rather old LT1013 is pin compatible to the LM358/4558, handles similar voltages and has precision but about 10-15x the cost.

There are op-amps with better (sometimes spectacularly better) specs than the above however there are often a gotcha or two such as limited supply voltage (some op-amps are limited to around 5V or lower maximum total supply voltage) or high price. For example, the TLV276x is recommended maximum 3.6V supply voltage (+/- 1.8V if you need bipolar supplies).

Spehro Pefhany
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I can only assume that you're using a 741 or similar because you need the offset null. If you need zero input offset voltage you can use a chopper op-amp like the OPA2180. Chopper opamps have an input offset of some microvolts.

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