hello everyone

I am working on a non inverting buck boost and the driver circuit is the ir2210. I want some help because in the boost mode I have a problem.
When the converter is in the boost mode, the high side MOSFET (S1) should always be on, and S2 is being switched on and off according to the desired output voltage ,so how can I guarantee that (S1) is always on in the boost mode with the IR2110?

 

The customary method of using the IR2110 is to switch the upper or high side Mosfet while holding the lower mosfet switch ON.
The switching of the upper side creates the charge pump.
Max.

 

The customary method of using the IR2110 is to switch the upper or high side Mosfet while holding the lower mosfet switch ON.
The switching of the upper side creates the charge pump.
Max.

Can you explain more . I already used the ir2210 to drive the converter when it was in the buck mode however when I needed to test the boost mode , I made short circuit from drain to source of the upper side mosfet. this was only for testing, now I need to do this with the ir2210 not a a short circuit, I want to keep the upper side switch always on in the boost mode

 

AFAIK you cannot obtain boost (Vb) with the upper side input always on.
Max.