Looking for op amp recommendations

Discussion in 'General Electronics Chat' started by JingleJoe, Dec 23, 2012.

  1. JingleJoe

    Thread Starter Member

    Jul 23, 2011
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    I have made a similar thread before but not only is it almost a year old, I'm looking for something a bit different now: any common and easy to find op amp with an output which can swing to the negative rail (which will be 0V or Ground in this case as I am operating on a single supply) and which has a better slew rate than the LM324.
    Ordinarily I'd use an LM324 or 358, they have been absolutely fine for all my other applications (TL074 op amps not functioninging properly in thier stead due to the output voltage swing limitations). I mostly operate at low frequencies and audio frequencies but recently I have had the need to operate at higher than usual frequencies and this is where the LM324 fell short.
    In the past I've used CA3140 op amps, but they are pricey and rather overkill for my simple applications.
     
    Last edited: Dec 23, 2012
  2. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    OPA743PA
    OPA340PA

    Both are available from Digikey, made by Texas Instrument (Burr Brown)

    About 2.50 USD each
     
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  3. Wendy

    Moderator

    Mar 24, 2008
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  4. Audioguru

    New Member

    Dec 20, 2007
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    I use the MC34071 opamp that costs $1.02 at Digikey today. The MC34072 is a dual and the MC34074 is a quad.
    They have a maximum supply of 44V, have low distortion full output swing up to 100kHz, have no crossover distortion like an LM324, have inputs that work at ground when there is a single supply and have outputs that go down very close to ground when there is a single supply.
     
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  5. JingleJoe

    Thread Starter Member

    Jul 23, 2011
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    Thanks for the recommendations chaps, they look great however they are from US providers, I can't find the same op amps from electronics providers in the UK.
    I also can't afford international postage for just a few op amps! :rolleyes:
    I looked up my old favorite the CA3140E and found this one (CA3240EZ) which is cheaper and similar but doesn't quite go all the way to ground :( so unfortunately it will not do but may be useful to add to that list Mr Marsden. Also I'd rather be able to get it in a quad (4 in 1) IC like the LM324 however dual (2 in 1) would be okay too, however the CA3240EZ dual comes in a 14 pin package :D too big for just two op amps, I don't need the extra offset nulling connections.
     
  6. bertus

    Administrator

    Apr 5, 2008
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  7. Audioguru

    New Member

    Dec 20, 2007
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    Go to www.farnell.com and click on the flag of your country. They BEGAN in the UK and sell everything.
     
  8. bertus

    Administrator

    Apr 5, 2008
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    Hello,

    Farnell is more made for business.
    As private people order over there, they have some rules.

    Bertus
     
  9. Audioguru

    New Member

    Dec 20, 2007
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    Newark was a huge American electronic parts distributor that got bought by Farnell. I am a private person and I ordered from them many times.
     
  10. atferrari

    AAC Fanatic!

    Jan 6, 2004
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    After reading the specs, from a post by Audioguru that suggested them, I bought some locally, from a Farnell representative.

    Using them right now in a project.
     
  11. JingleJoe

    Thread Starter Member

    Jul 23, 2011
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    Thanks chaps, I ordinarily use rapid and a small supplier with really cheap post; www.spiratronics.com
    I've heard of farnell before but I disregarded them because I thought they have a minimum order of £50 or something like that? I also avoid maplin because they are more expensive. I'll look into them both, however if I can't find something on rapid I tend not to be able to find it anywhere else. I'll keep looking but does anyone have any more recommendations? One can't get enough options when it comes to components :)

    UPDATE: I just checked farnell, they say in one place that they have no minimum orders however in the fine print thay say "£20 minimum order value applies to all credit card orders".
     
    Last edited: Dec 24, 2012
  12. KrisBlueNZ

    Member

    Oct 17, 2012
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    I also use and recommend the MC34071/2/4 devices. Easy to use, good performance, and no crossover distortion! And cheap.
     
  13. Audioguru

    New Member

    Dec 20, 2007
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    In addition to the normal power MC340xx opamps I also use the low power MC33171 single, MC33172 dual and MC33174 quad opamps.

    They work from a supply as low as 3V like an LM358 or LM324 and have exactly the same low power supply current. Also their max power supply voltage is much higher than the old ones.
    But they have NO crossover distortion and have a full output bandwidth to 35kHz compared to only 2kHz from an old LM358 or LM324.
     
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