STDA017 November   2025 TPS7A33 , TPS7A4501-SP , TPS7A47 , TPS7A47-Q1 , TPS7A4701-EP , TPS7A52 , TPS7A52-Q1 , TPS7A53 , TPS7A53-Q1 , TPS7A53A-Q1 , TPS7A53B , TPS7A54 , TPS7A54-Q1 , TPS7A57 , TPS7A8300 , TPS7A83A , TPS7A84 , TPS7A84A , TPS7A85A , TPS7A90 , TPS7A91 , TPS7A92 , TPS7A94 , TPS7A96 , TPS7B7702-Q1 , TPS7H1111-SEP , TPS7H1111-SP

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction to Parallel LDOs Using Ballast Resistors
  5. 2Noise Analysis of Parallel LDOs Using Ballast Resistors
  6. 3LDO Output Impedance
  7. 4Strategies on Reducing the Noise of the Parallel LDO System
  8. 5Noise of Parallel LDOs Using Ballast Resistors
    1. 5.1 TPS7A57
    2. 5.2 TPS7A94
  9. 6Noise Measurements of Alternative Parallel LDO Architectures
    1. 6.1 TPS7B7702-Q1
  10. 7Conclusion
  11. 8References

7 Conclusion

This document compares and contrasts the noise performance of three common parallel LDO techniques. For the first time, the technical foundation for noise reduction in parallel LDOs using ballast resistors is discussed while demonstrating that other techniques do not provide the same noise advantage. Designers can now architect the correct parallel LDO architectures to meet specific design requirements, including ultra low noise specifications, when no single LDO can meet the noise specification alone.