SLVA469D June   2013  – January 2023 TLV62130 , TLV62130A , TLV62150 , TLV62150A , TPS61175 , TPS61175-Q1 , TPS62130 , TPS62130A , TPS62131 , TPS62132 , TPS62133 , TPS62135 , TPS62136 , TPS62140 , TPS62140A , TPS62141 , TPS62142 , TPS62143 , TPS62150 , TPS62150A , TPS62151 , TPS62152 , TPS62153 , TPS62160 , TPS62161 , TPS62162 , TPS62163 , TPS62170 , TPS62171 , TPS62172 , TPS62173

 

  1.   Using the TPS6215x in an Inverting Buck-Boost Topology
  2.   Trademarks
  3. 1Inverting Buck-Boost Topology
    1. 1.1 Concept
    2. 1.2 Output Current Calculations
    3. 1.3 VIN and VOUT Range
  4. 2Design Considerations
    1. 2.1 Design Precautions
    2. 2.2 Additional Input Capacitor
    3. 2.3 Digital Pin Configurations
      1. 2.3.1 Digital Input Pins (EN, FSW, DEF)
      2. 2.3.2 Power Good Pin
    4. 2.4 Startup Behavior and Switching Node Consideration
  5. 3External Component Selection
    1. 3.1 Inductor Selection
    2. 3.2 Capacitor Selection
  6. 4Typical Performance
  7. 5Conclusion
  8. 6References
  9. 7Revision History

3 External Component Selection

The inductor and output capacitor must both be selected based on the needs of the application and the stability criteria of the device, which are different from the traditional buck converter approach.  A load transient test should be performed to evaluate stability.  Figure 4-9 shows the results of such a test performed on the example circuit.  The lack of ringing indicates stability.