There are dedicated "MOSFET driver" IC's available . Some also control IGBTs. What is the practical purpose of these? Is it all about maximizing the switching speed (driving gate capacitance) or are there other motives?

 

The main purpose is to provide level shifting and high current drive to charge and discharge the gate capacitance as rapidly as possible.

 

Also Check out Tahmids blog for a description of the IR2110.
http://tahmidmc.blogspot.ca/2013/01/using-high-low-side-driver-ir2110-with.html
Max.

 

Yes, providing the drive current to charge/discharge the gate capacitance for purposes of switching speed.

 

The gate driver IC does an excellent job of delivering high current pulses, cheaper, faster, and smaller than you can do it with single transistors.

 

They also allow you to use N channel MOSFETs for high side switches.

Bob

 

For the cap calculator
https://www.silabs.com/support/Pages/bootstrap-calculator.aspx
Max.