High side drive

[Dreamer1]

Ok, so here is my problem

I have a buck-boost circuit and i'm having trouble driving the high-side mosfet. Problem is, my input range is 6V-35V. Initially we wanted to use a voltage doubler, but unfortunately at 6V input voltage would result in 12v (theoretical), and this 12V would not be enough to drive the mosfet we have picked  as we want at least 10V VGS, hence 6V in, 16V - > vgs.

Does anyone have any ideas how I can get around this problem? A nice chip that has an output function such as

X volts in,
X+10 Volts out over a large voltage range?

[poorchava]

I think all the chips use single stage bootstrap. You would need too.  I guess you can make your own 2-stage multiplier and then switch it to the gate.  Or you can look for mosfet with lower vth,  or you can use a p - channel one.

[Kremmen]

Or use a proper high side driver chip. Such as the IR 21xx family.

[Pezo]

An IR21xx wouldn't really help, if the input voltage is 6V then so is the gate drive voltage.

[poorchava]

What are your requirements for the switch? That would really help.