THE FEUTEX TOOLKIT

Op-Amp Bias Resistor Balance

Compute the balancing resistor and remaining offset-current error.

Electronics workspace● Runs in your browser

01 Your input

Input resistorohmFeedback resistorohmOffset current magnitudeAVoltage offset magnitudeV

02 Your result

View or copy raw result data

Result data

FormulaRb=Rin∥Rf; |Verror|≈IosRf+Vos NG

Sources and model references

https://wiki.analog.com/university/courses/electronics/text/chapter-3

Worked example

Inputs

Input resistor: 1000 ohm
Feedback resistor: 9000 ohm
Offset current magnitude: 1e-08 A
Voltage offset magnitude: 1e-05 V

Expected results

Balancing resistance: 900 ohm
Worst-sign residual offset: 0.00019 V

Load the example in the workspace to reproduce these results. Display rounding does not change the underlying calculation.

How to use this tool

Enter the labeled inputs in the indicated units.
Calculate and compare every output against the stated model assumptions.

Try this example

{
  "ri": 1000,
  "rf": 9000,
  "ios": 1e-8,
  "vos": 0.00001
}

Accuracy and scope

Assumes equal mean bias currents and ideal balancing; input source resistance included in Rin. Simplified analytical model; not a design recommendation or safety certification.

Is my data uploaded?

This tool runs locally in your browser. Input and output are not sent to a processing server. Copy or download your result before leaving the page.