SLUAAV0A April   2024  – November 2025 UCC27301A-Q1 , UCC27311A-Q1 , UCC27517 , UCC27517A , UCC27517A-Q1 , UCC27524 , UCC27614 , UCC27624 , UCC27624-Q1 , UCC27710 , UCC27712 , UCC27712-Q1 , UCC27714 , UCC27734 , UCC27735 , UCC44273 , UCC57102 , UCC57102-Q1 , UCC57102Z , UCC57108 , UCC57108-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2PFC Stage
    1. 2.1 Boost PFC
    2. 2.2 Interleaved Boost PFC
  6. 3Motor Drive Stage
    1. 3.1 Standalone Gate Drivers vs. IPM
    2. 3.2 Driving Three-Phase Motors
    3. 3.3 Higher Power Levels for Commercial HVAC
  7. 4DC/DC Stage
    1. 4.1 Synchronous Buck Converter
    2. 4.2 Flyback Converters
  8. 5Summary
  9. 6References
  10. 7Revision History

4 DC/DC Stage

DC/DC switching converters in HVAC systems are used to efficiently shift voltage levels for different applications. Like motor drives, there are different integration levels to consider when designing DC/DC converters, from standalone gate driver IC to full integration. The advantages in selecting a gate driver IC to drive power devices is akin to selecting a gate driver IC to drive motor drives. To summarize, gate driver ICs can provide better thermal performance, potential for higher power, and less EMI with proper PCB layout.

Switching efficiency is a critical requirement for DC/DC converters in HVAC systems. Compared to motor drivers, DC/DC converters run at a much higher switching frequency. Higher switching frequencies reduces output ripple and the size of transformers and inductors, but often with the caveat of switching losses. A gate driver with high peak currents is often sought after when selecting a gate driver to drive DC/DC converters, as high peak currents can allow for a faster rise and fall time, which reduces switching losses for an increase in system efficiency.