DRV8432: External BST Bootstrap supply: Design requirements

Felix Risch25

Part Number: DRV8432

Hello together,

one of my customer needs to supply the HS gate drivers of the DRV8432 with an external isolated voltage source instead of using the bootstrap circuit.

Do we have a guideline for that? What are the limitations we need to consider?

Thank you and kind regards,

Felix

over 8 years ago

0 Rick Duncan over 8 years ago

TI__Guru** 114905 points

Hi Felix,

Can you clarify this? Is the desire to operate the device at 100% duty cycle (which requires a separate VM + 12V source) or to power the bootstrap circuits separately (requires a second 12V source)?

0 Felix Risch25 over 8 years ago in reply to Rick Duncan

TI__Intellectual 1110 points

Hi Rick,

yes, the customer wants to reduce the switching frequency / increase the duty cycle where our device is out of specification for correct recharging the Bootstrap capacitor.

Kind regards,

Felix

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DRV8432: External BST Bootstrap supply: Design requirements