JAJSQS4C July 2023 – April 2024 TPS7H6003-SP , TPS7H6013-SP , TPS7H6023-SP
PRODUCTION DATA
The external bootstrap capacitor that is required for the driver is connected between BOOT and ASW. The bootstrap capacitor voltage serves as the input to the high-side linear regulator BP5H that provides the gate drive voltage for the high-side GaN FET. A general guideline for bootstrap capacitor selection is that its value should be at least 10× greater than the gate capacitance of the high-side GaN FET that is being driven:
where:
A more detailed calculation of the minimum bootstrap capacitance needed can be found using Equation 2:
where:
and ∆VBOOT is the maximum allowable drop on BOOT for proper operation:
where:
Selection of a bootstrap capacitor with low ESR and ESL is recommended. The voltage rating of the bootstrap capacitor should have sufficient margin above the maximum expected bootstrap voltage.