I want to use a MOSFET to switch 400V to a circuit. I can switch low-side using an n-channel MOSFET, but it's more convenient to have the circuit with its ground fixed. So I want to switch high-side, but I don't see how I can use a low voltage for the switching (0 - 5V).
I am switching with a 0/5V square pulse and I need Vsg > |Vt| for the switch to be on (i.e. my load is to be connected to Vdd = 400V). With the configuration below, the MOSFET will be on regardless of if I have a HIGH or a LOW on my input pulse.
Does this mean my switching pulse needs to be 0/400V square pulse (a 400V on gate would give Vsg = 0V < |Vt|, turning the FET off)?
My MOSFET: 500V infeneon IPW50R190CE Switching frequencies: 10 MHz