Try to understand how the bootstrap capacitor is charged. I think it is pretty much well explained in the link I sent.

Re http://forum.allaboutcircuits.com/newreply.php?do=newreply&p=576567

Old Post, but does this confirm that in a MOSFET full bridge the upper FET can be kept on and the bottom switched for recharging VB?
I get conflicting stories!
Also lower and opposite upper cannot be kept on 100%, due to no VB generated?
Max.

 

The upper capacitor is charged when the lower mosfet is switched on.
It will eventually lose charge if not refreshed.

 

I am getting different opinions from various sources?
One says both upper and lower have to be PWM switched, others as the link seems to imply, that the upper side can be switched on and the low side PWM'd?
Max.

 

Anyone use the Pic ECCP module with the IR2110?
The ECCP module examples for DC motor full bridge shows one output switched high and the other modulated.
If anyone has used this with the IR2110, what configuration did you use?
High or low mosfet modulated, if at all?
Max.