SLVAFQ5 December   2023 TPS51383 , TPS51385 , TPS51386

PRODUCTION DATA  

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Zcap Calculation of Hybrid Capacitors
  6. 3Experimental Verification
  7. 4Loop Stability Analysis With Hybrid Output Capacitor Network
  8. 5Application Design Example of D-CAP3 Converter With a Hybrid Output Capacitors Network
  9. 6Summary
  10. 7References

Abstract

D-CAP2™ and D-CAP3™ converters achieve low ESR ceramic output capacitors through ripple injection circuit. But many designers still prefer to use an electrolytic capacitor or polymer to obtain high capacitance for better ripple and transient performance. This application note discusses the loop stability of the D-CAP2 and D-CAP3 converter using different types of capacitors, especially electrolytic capacitors or polymers. This application note introduces the calculation of the zero and pole with a hybrid output capacitor network based on D-CAP2 and D-CAP3 stage small signal model. The theoretical calculation results are verified by bench loop test. An analysis of the loop stability for the D-CAP2 and D-CAP3 converter with a hybrid output capacitors network is provided. This application note also provides two application design examples based on TPS51386EVM, a 4.5-V to 24-V input, 8-A synchronous buck converter with adaptive on-time D-CAP3 control mode.