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LM101A-N: LM101A bias currents over temperature

Part Number: LM101A-N
Other Parts Discussed in Thread: LM148, LM1558

I am analyzing an old design for robustness/possible improvements that uses the LM101A op-amp. The datasheet includes the Average Temperature Coefficient for the input offset voltage and current, but does not include a similar maximum for the bias currents. Is such a maximum available? If not, is a typical number available?

Thank you,

- Clare

  • Clare,
    The engineer that supports this device is on travel. He should be able to respond to you shortly.
    Regards,
    Wade
  • Thanks for the update!

    Does the same engineer also support the LM108A, LM148 and MC1558? If so, are the average & max temperature coefficients for the voltage offset, current offset, and bias current over temperature available?

  • Hello Clare,

    To get an idea of the of how these commercial products behave over temperature, visit the military datasheets for these products, which have limits over the full temperature range.   The military prooduct pages and datasheets for these products end in "QML".

    It is likely that the commercial versions of the parts will have distributions well within in those limits, but we don't test commercial parts over temperature and cannot guarantee it.   The mil grade parts are tested over the full temperature range.

    www.ti.com/.../lm1558qml.pdf

  • Hello Clare,
    I should clarify something else.
    TI acquired National Semiconductor in 2011 and still offers both National and TI versions of some parts. The MC1558 is of TI origin but matches up with the LM1558. For many of the TI parts, the commercial and mil specs are shown on the same datasheet as is the case with the MC1558. You can find the performance over temp on that datasheet.

    TI no longer offers a versions of the LM108.
  • Kirby,

    The LM148J mil temp range spec had Temperature Coefficients for the offset voltage and offset current. However, I don't see either spec in the 1558 datasheet linked.

    We are not using the 108A in new design, but I am analyzing the capabilities of an older unit and would appreciate a datasheet with these values.

    I have not seem a temperature coefficient for bias currents in any of the datasheets. Is there any documentation on how much this it is expected to vary over temperature?

    Thanks,
    Clare
  • All we have it is what is in the datasheets. For temp coefficients, the only thing you can do is infer is worst case from the limits changes at hot and cold. We are not able to pull data that would demonstrate the temperature coefficients.