SNVAA63 March   2023 TPSM365R6

 

  1.   Abstract
  2.   Trademarks
  3. 1Inverting Buck-Boost Topology
    1. 1.1 Concept
    2. 1.2 Output Current Calculations
    3. 1.3 VIN and VOUT Range in Inverting Configuration
  4. 2Design Considerations
    1. 2.1 Additional Bypass Capacitor and Schottky Diode
    2. 2.2 Start-up Behavior and Switching Node Consideration
  5. 3External Components
    1. 3.1 Capacitor Selection
    2. 3.2 System Loop Stability
  6. 4Typical Performance
  7. 5Digital Pin Configurations
    1. 5.1 Digital Input Pin
    2. 5.2 Power-Good Pin
  8. 6Conclusion
  9. 7References

3 External Components

The TPSM365R6 contains integrated power MOSFETs and a shielded inductor. As a result, the inverting buck-boost application only requires as few as four external components. The required external components are its input and output capacitance as well as an appropriately sized bypass capacitor. When using the TPSM365R6 EVM, most of these required components are already included; however a new set of input capacitors are required to be placed between the VIN and VOUT pins. TI also recommends that the bypass capacitor between the VIN and the TPSM365R6 IC GND pin be increased in capacitance to improve the inverting buck-boost's load transient performance. More information about these components can be found in Section 2.1 and Section 3.2 as well as in the TPSM365R6's data sheet. Performing a load-transient test and frequency sweep is recommended to evaluate stability.