I am reading a data sheet that has offset current at 200nA, however, some calculations are using the total offset current.

Why does the op-amp image below half the Offset current?


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    \$\begingroup\$ You should post the relevant datasheet link and refer to specific parts of the datasheet. \$\endgroup\$ – Spehro Pefhany Mar 29 at 4:03
  • \$\begingroup\$ It is more a general question about calculations when using offset current rather than a datasheet question. \$\endgroup\$ – Roo Mar 29 at 4:06
  • \$\begingroup\$ I don't see this "halving" of which you speak. What calculations exactly are you referring to. \$\endgroup\$ – Spehro Pefhany Mar 29 at 4:16
  • \$\begingroup\$ Do you have a question? \$\endgroup\$ – AnalogKid Mar 29 at 4:22

Looks like a mistake.

Ibias = (Ibp+Ibn)/2

Ios = Ibp - Ibn

Where Ibp is the current flowing into the non-inverting input and Ibn is the current flowing into the inverting input.


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