SDAA460 July   2026 ISOUSB211

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Power Pins and Internal Rails
  6. 3Available Supply Options
    1. 3.1 Generating the 3.3V Rail (V3P3Vx)
    2. 3.2 Generating the 1.8V Rail (V1P8Vx)
    3. 3.3 Summary of the Four Building Blocks
  7. 4Typical Example Power Configurations
    1. 4.1 Power Configuration for an Isolated Host or Hub (Mixed Internal and External)
    2. 4.2 Power Configuration for Isolating a Self-Powered Peripheral
    3. 4.3 Power Configuration for Isolating a Bus-Powered Peripheral
  8. 5Thermal Considerations When Selecting a Supply Configuration
    1. 5.1 Operation Without External 1.8V Supply
    2. 5.2 Operation With External 1.8V Supply
  9. 6References
  10. 7Revision History

3.3 Summary of the Four Building Blocks

Rail Internal-LDO Option External-Supply Option
3.3V (V3P3Vx) 4.25–5.5V into VBUSx
LDO generates 3.3V		 VBUSx + V3P3Vx shorted to external 3.3V supply
1.8V (V1P8Vx) 2.4–5.5V into VCCx
LDO generates 1.8V		 VCCx + V1P8Vx shorted to external 1.8V supply