H-Bridge Design: MOSFET Gate Charge

May 20, 2005 3 Replies

How does the Gate Charge of a FET relate to the bootstrap capacitor value. I am changing out the FETs in my present design, for ones with considerably larger Gate Charge.



Does the increase in max Gate Charge simply mean I need to use a larger capacitor to supply this charge/support the gate?



MEP



If you wish; the capacitor should be >> Ciss. The commonly-used 0.1uF is more than enough.

Thanks, - Win

IR do a nice app note on this topic.

Graham

And watch your rise and fall times.

Robert

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required