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

5 Conclusion

The TPS6215x buck dc-to-dc converter can be configured as an inverting buck-boost converter to generate a negative output voltage. The inverting buck-boost topology changes some system characteristics, such as input voltage range and maximum output current. This application report explains the inverting buck-boost topology and how to select the proper values of external components with the changed system characteristics. It also gives design guidelines and precautions to ensure the robust operation of the converter. Measured data from the example design are provided. This application report also applies to any of the devices in the TPS6213x/4x/5x/6x/7x families.