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OPA4188: OPA4188

Prodigy 20 points

Replies: 3

Views: 191

Part Number: OPA4188

Is there an issue with having one of the inputs powered (about 2.5Vdc) and no power on the supply pins?

  • Richard,

    In general we advise against applying voltages to op amp pins when the supplies are off. It is an unspecified and uncharacterized circuit condition that might have unexpected consequences when the power supply pins do come up.

    When there is no power applied to the OPA4188 supply pins V+ and V- do those pins see a high impedance back through the unpowered supplies? Also, will there be any resistance between the input(s) and the +2.5 V voltage source?

    Regards, Thomas
    Precision Amplifiers Applications Engineering
  • In reply to Thomas Kuehl:

    Yes, the supply pins see a high impedance when off. And yes there is high impedance looking back at the 2.5V input (> 30meg ohms).

    Regards,

    Richard

  • In reply to Richard Werber:

    Hi Richard,

    Officially, TI doesn't provide any assurances about a particular device's behavior for any electrical condition that isn't covered in the Electrical Characteristics table. Unofficially, the fact that the OPA4188 is being driven by a very high source impedance in the unpowered state that very little input current could be sourced. It is highly unlikely that the unpowered OPA4188 would respond in any negative way to this set of conditions.

    Regards, Thomas

    Precision Amplifiers Applications Engineering

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