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LTC3649 Top and bottom switch gate charge

Hi. To calculate a switching loss for LTC3649 I need to know gate charge of top and bottom power switches, but this information is not provided in datasheet. How should I evaluate switching loss?

  • I got it by myself. Maybe it'll be usefull. The current that is being supplyed by EXTVcc pin at 1MHz is known and it is 20mA. The formula for this current is:

    Now the current for any frequency can be calculated as the proportion, and we don't need to know Qt and Qb.

    Igatechg = (20mA*f )/ 1MHz