SLUA887A August   2018  – September 2023 UCC27710 , UCC27712 , UCC27714

 

  1.   1
  2.   Bootstrap Circuitry Selection for Half-Bridge Configurations
  3.   Trademarks
  4. 1Introduction
  5. 2Basic Operation of Bootstrap Circuit
  6. 3Bootstrap Components Selection
    1. 3.1 Bootstrap Capacitor
    2.     8
    3. 3.2 VDD Bypass Capacitor
    4. 3.3 External Bootstrap Diode
    5.     11
    6. 3.4 Bootstrap Resistor
    7.     13
  7. 4Layout Considerations for Bootstrap Components
  8. 5Summary
  9. 6References
  10. 7Revision History

3.4 Bootstrap Resistor

The role of the bootstrap resistor is to limit the peak currents at the bootstrap diode during start-up, it should therefore be carefully selected as it introduces a time constant with the bootstrap capacitor given by Equation 6:

Equation 6. τ = R Boot × C Boot Duty   Cycle