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Asking for Op Amp recommendations

  1. Feb 25, 2015 #1
    Hi all,
    I realize I'm asking for the world here, but google hasn't been very helpful. I've found a few candidates with some/most of what I need, but wondering if there is some holy grail op amp out there that everyone is using. I'm growing tired of making work-arounds for the LM324's I have laying around.

    I'm looking for a commonly available op amp (or multi opamp package), 8-pin to 14-pin dip with the following attributes.

    Rail-to-rail capable.
    Single supply or dual supply.
    Can source or sink about 20 mA.
    Has internal protection for common-mode input voltage beyond supply voltages.
    Has internal protection for differential input voltage beyond supply voltages.
    (And the usual, internal, ESD protection.)
    Output does not exhibit phase reversal when inputs are beyond supply ranges.
    Preferrably robust for harsh environments and not requiring a lot of anti-ESD precautions during handling.

    I don't need very high freq capability, probably audio range or even slightly less.

    I just find my projects are always limited on space, hence the internal protection components would be nice. It usually ends up in automotive type environments.

    One thing I haven't found, so am wondering if it even exists, is internal protection for input voltages where the protection doesn't greatly affect the input impedance. I realize this feature might be physically impossible, but in case there is some magic op amp out there, I thought I'd ask.

    Thanks for any help.
     
  2. jcsd
  3. Feb 25, 2015 #2

    Svein

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    Science Advisor

  4. Feb 25, 2015 #3
    Thanks, that is a handy little page indeed.
     
  5. Feb 25, 2015 #4

    berkeman

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    Staff: Mentor

    In addition to the Linear Technology link, have a look at the Maxim website (www.maxim-ic.com) and at TI's website. They will have product selector features that will help you home in on some good candidates. Then use Digikey's website to check pricing and availablity.

    BTW, I don't think you will find much beyond basic IC ESD protection in opamps. They are not usually exposed to an external human-contact environment like transceiver chips are.
     
  6. Feb 26, 2015 #5
    You might look at the LMC6041 (LMC6041AIM/NOPB). It is almost an "ideal" op-amp for under $2.00. I've found them very useful for high impedance circuits and where rail-to-rail operation is desired. Check: http://www.ti.com/product/lmc6041
     
  7. Feb 26, 2015 #6
    Thanks again,
    I did find a Maxim product line with almost exactly the internal protections I was looking for, but unfortunately, the line is also "Micropower" which means very low output (less than 1mA). It also only handles 5v as the supply. But it makes me hopeful something is out there with this type of, what Maxim calls, "Beyond-the-rails" input operation.

    The LMC6041 looks pretty good too, (albeit, without protection for inputs "beyond-the-rails"). But rail-to-rail, and 18 mA output, still makes it useful to me for other projects.
     
  8. Feb 27, 2015 #7
    I thought I found it with this one, but realized I needed a faster slew rate than I first thought (for the current project). I probably need more like .5v/usec. This one is .07v/usec.
    http://cds.linear.com/docs/en/datasheet/14901afd.pdf
    Everything else about it sounds good.
     
  9. Mar 4, 2015 #8
    Well, after going through quite a few data sheets I ordered some LM6142's. Turns out, the hardest feature to get, anymore, is the 8-pin dip footprint. Making stuff at home is only going to get more difficult, apparently. But Digikey still had some 8pin dip versions in stock.

    http://www.ti.com/lit/ds/snos726d/snos726d.pdf

    I had to give up on some of the internal input protection features but otherwise it looks pretty good.
     
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