SBOA586 February   2024 OPA182 , OPA186 , OPA187 , OPA188 , OPA189 , OPA333 , OPA387 , OPA388

 

  1.   1
  2.   Abstract
  3. Benefit of Zero-Drift Amplifiers
  4. Internal Operation of Choppers
  5. Chopping Input Current Transients
  6. Bias Current Translation Into Offset
  7. Chopping Current Transient Impact on Offset Voltage
  8. Input Bias Current versus Bias Transients
  9. Amplifier Intrinsic Noise
  10. Chopper Transient Noise
  11. Procedure for Selecting a Zero-Drift Amplifier
  12. 10Summary
  13. 11References

Summary

Zero-drift amplifiers have many benefits when compared to traditional precision amplifiers. Most notably, the offset and offset drift of zero-drift amplifiers are usually substantially better than similar traditional amplifiers. However, there are some error sources related to the internal switching of the chopper calibration circuit. In many cases the chopper errors are not significant. Section 9 lists a procedure that provides guidance in the selection of the zero-drift amplifier and the associated discrete components to minimize these errors.