SLUUCF8 March   2021 TPS53676

 

  1.   Trademarks
  2. 1 Introduction
  3. 2 Features
  4. 3 Applications
  5. 4 System Description
    1. 4.1 Phase configuration selection
    2. 4.2 Jumper details
    3. 4.3 On-board load transient
  6. 5 Test Equipment
  7. 6 Test Procedure
    1. 6.1 Start-up Test
    2. 6.2 Shut down Test
    3. 6.3 Steady-state Test
    4. 6.4 Load Transient Test
    5. 6.5 Efficiency Plot
    6. 6.6 Bode plot
  8. 7 Fusion GUI
  9. 8 Evaluation Module (EVM) Hardware
  10. 9 Schematic and Bill of Materials
  11. 10Read This First
    1. 10.1 About This Manual
    2. 10.2 Glossary
    3. 10.3 Related Documentation
    4. 10.4 Support Resources

6.6 Bode plot

The EVM includes a provision to also perform a Bode plot to examine the control loop stability. To perform this test, a Spectrum analyzer is required. The resistor R10 (RAILA) or R13 (RAILB) must be replaced with an appropriate terminating resistor (usually 10 Ω or 20 Ω). The signal must be connected to parallel to R10 or R13. The loop gain is measured using the spectrum analyzer. Figure 6-14 and Figure 6-15 shows a measurement of the Bode plot made on this EVM for RAILA and RAILB.

GUID-89BA94B2-DBF4-4E29-8B57-4AE545A6972E-low.pngFigure 6-14 VOUTA Bode plot, Load current=50A
GUID-B11C4470-AF7B-447E-ADDB-409FA3F33C06-low.pngFigure 6-15 VOUTA Bode plot, Load current=20A