SLUAAF4A may   2021  – april 2023 TPS51397A , TPS53318 , TPS53319 , TPS53353 , TPS53355 , TPS548A28 , TPS548A29 , TPS548B22 , TPS548B28 , TPS548D22 , TPS549B22 , TPS549D22 , TPS54J060 , TPS54J061 , TPS54JA20 , TPS54JB20 , TPS566235 , TPS568215 , TPS568230 , TPS56C215 , TPS56C230

 

  1.   Abstract
  2.   Trademarks
  3. 1D-CAP Feedback Loop
  4. 2D-CAP Bode Plot Measurement Setup
  5. 3Bode Plot Measurements
  6. 4Transient Response Waveforms
  7. 5D-CAP2 and D-CAP3 Bode Plot Measurement Setup
  8. 6Measurement Tips
  9. 7Summary
  10. 8References
  11. 9Revision History

6 Measurement Tips

To obtain a good Bode plot measurement, it is important to pay attention to the setup and take precautionary steps to reduce measurement errors. Some basic recommendations are:

  • Before taking the measurement, calibrate the network analyzer or do a 0-dB measurement to ensure flat gain and zero phase across the frequency range of interest.
  • Use the analog ground of the controller or converter as the reference for the Bode plot probes.
  • Keep the probes far away from the inductor to avoid coupling the inductor magnetic-field signal onto the AC injection magnitude.
  • If possible, use the resistive power dissipation at the load connection instead of the electronic current source mode.