TPS54302: How large boot resistor is acceptable?

Hideki Hayashi1

Part Number: TPS54302

Hi team,

How large boot resistor is acceptable?

What is the trade-off of boot resistor? (I think current consumption increase?)

Regards,

Hayashi

0 Miranda Gu over 2 years ago

Hi Hayashi,

No need to use boot resistor in tps54302 reference circuit.

If you want to add it to control SW ringing, suggest to start from several ohms.

Large Rboot will increase switching loss, and could affect BOOT-SW voltage (related to BOOT-SW UVLO protection).

0 Hideki Hayashi1 over 2 years ago in reply to Miranda Gu

Hi Miranda,

Yes I know it is for reduce ringing. Is the 33ohm boot resistor accetable?

Miranda Gu said:
could affect BOOT-SW voltage (related to BOOT-SW UVLO protection).

If customer keeps BOOT-SW votlage within the ABS max, is there no other ristriciton, right? (-0.3V < BOOT-SW < 7V)

Regards,

Hayashi

0 Miranda Gu over 2 years ago in reply to Hideki Hayashi1

Hi Hayashi,

When BOOT-SW voltage decreased to less than 2.1V (typ.), device will trigger BOOT_UV.

Could you please measure BOOT-SW waveforms during normal operation? This AN gives a guidance.

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