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OPA4277: What is modern replacement of OPA4277 chip?

Andrzej Szupiluk
Prodigy 230 points
Part Number: OPA4277
Other Parts Discussed in Thread: OPA4192, OPA4196, OPA4188, OPA277, OPA2277, OPA4388
Hi,
In my application I use a few OPA4277 chips.
Sometimes I have to make manual offset correction of some amplifiers
due to big factory input offset voltage.
My question is: what is modern replacement for OPA4277 chip?
Requirements:
1) Power ±7V, max. 0.8mA per amplifier.
2) Input signal 0-10Vpp, sine 20-25kHz.
3) Offset and drift better than OPA4277.
4) Price <= of OPA4277.
Regards
Andrzej
  • 0
    Guru 48395 points

    Well the TI cross reference points to the 

    OPA4192 or

    OPA4196

  • 0 in reply to Michael Steffes
    Prodigy 230 points

    Hi, Michael

    Thanks.

    But:

    1) OPA4192 has many times greater nose at low frequencies.

    2) OPA4196 has 5 times greater offset and drift.

    Other propositions?

    Regarsds

    Andrzej

  • 0 in reply to Andrzej Szupiluk
    TI__Guru 63010 points

    Andrzej,

    In order to help you, please include a full list of all your requirements.  In the list below, you do not say anything about max offset voltage or noise so it is difficult to know what your actual requirements are.  OPA277 is a bipolar input op amp so its 1/f (low frequency voltage noise) will be better than CMOS op amps like the one mentioned above but its input current noise will be much worse.  If you need a better input voltage offset and no 1/f input voltage noise, please take a look at OPA4188.

    Requirements:
    1) Power ±7V, max. 0.8mA per amplifier.
    2) Input signal 0-10Vpp, sine 20-25kHz.
    3) Offset and drift better than OPA4277.
    4) Price <= of OPA4277.

  • 0 in reply to Marek Lis
    Prodigy 230 points

    Hi Marek

    I use OPAx277 in a few places, but at now we will consider the first:

    1) Supply +6.5V - only, (but better will be 5.5V).

    2) It generates static reference voltages 2.44V and 4.88V from prec. source 2.5V.

    3) Low frequency output noise should be minimized and temp. drift as well.

    4) Capacitive load will be desirable.

    5) Price  - near OPA2277.

    Regards

    Andrzej

    PS. I have many problems with analog circuit due to death of my partner and now I must take this duty …

  • 0 in reply to Andrzej Szupiluk
    TI__Guru 63010 points

    As I mentioned before, a modern higher precision replacement for OPA4277 would be OPA4188.  But if you can use 5.5V supply (absolute max 7V) and tolerate higher IQ, the best alternative would be OPA4388.

  • 0 in reply to Marek Lis
    Prodigy 230 points

    Hi Marek

    Thanks. I'll try to test and use these new chips.

    Best regards 

    Andrzej