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INA149: minimum input bias current

Part Number: INA149

Hello,

I am curious what the minimum input bias current for IN+ and IN- for this amplifier is. I have very high resistance on the input sources and want to make sure that there will be enough current for the amplifier to still function.

thanks

  • Hello Marshall,

    Thank you for your post. I can help you. Input bias current is not a spec that we include in the datasheet because the INA149 is a difference amp with input resistors. This means the input current is a function of the input differential voltage.

    You can simulate this based on your input differential voltage. You can put an ammeter in series with your input differential voltage. You may sweep the input differential voltage and plot the input current accordingly. The TINA spice model can be found and downloaded here: http://www.ti.com/product/INA149/toolssoftware

    -Tamara