Electronic – Always ON high-side MOSFET driver

drivermosfet

In a high voltage application (30-40V) am looking to drive a high side MOSFET which is sometimes required to be some for considerable amount of time (hours or days). [Edit] It is shown in the block diagram below.

High-side MOSFET

If I've understood correctly a bootstrap driver for a NMOS won't work in this case, right? Are there any other ways for driving high side NMOS which would require at times to be permanently on?

What about PMOS driver? When switching off it needs to connect to the supply voltage but for turning off its gate needs to be supplied around 10V below the supply voltage since connecting to GND will exceed the Vgs limit.
Any idea how to do this? Any commercially available IC?
Thanks a lot!

Edit: The circuit shown below works for switching a high side PMOS, albeit with some power loss and not at high frequency. If anyone knows any way to achieve higher frequency (100kHz), please let me know.

Best Answer

Using Andy's and some other people's suggestion here is the solution that I've come up with

Part of a schematic dealing with PMOS switching

The pro of this approach is the simplicity, but the cons are that the driving speed is limited and the power consumed when the PMOS is ON.

Edit: More clarification: OutConn- can be any source voltage (Vcc). PGate2 is the connection to the PMOS gate to switch it. After actually testing this circuit, i can say that for a power MOSFET with gate capacitance of about 3000pF the switching frequency that can be achieved can be maximum of about 1kHz. If anyone knows how to achieve higher frequency, please let me know.

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