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This is the circuit:

My question is: how can I send signals to the high-side MOSFET driver?

I thought about this way:

But "B" may be 0 V when the MOSFET is on, resulting in a negative voltage on the driver's input (assuming the input's ground is high voltage)

Am I right? If I'm right, how can I drive the high-side driver properly?

EDIT:

What do you guys think about this way (added in green - resistor voltage divider and a fast diode), will it work?

How do they do it in their ICs? Isn't it called "level shifting"?

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    \$\begingroup\$ You could use one of the many chips that are designed to do this job. \$\endgroup\$
    – Andy aka
    Commented Dec 29, 2022 at 17:06
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    \$\begingroup\$ IRS2181 is 1.5/1.8A, is that enough? How about LF2110BTR, LF21904NTR, FAN7393A, etc.? The charge pump can be added onto any bootstrap type driver just fine. \$\endgroup\$
    – Tim Williams
    Commented Dec 29, 2022 at 19:33
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    \$\begingroup\$ 12A?! Just what are you doing? Is bootstrap really the best way to go here? \$\endgroup\$
    – Tim Williams
    Commented Dec 30, 2022 at 2:10
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    \$\begingroup\$ @Tim There's nothing fundamentally wrong with a 12A peak gate current. The gate drive pulse is brief. The large(ish) value may be due to a large geometry of the gate, or multiple IGBTs in parallel. \$\endgroup\$
    – Nick Alexeev
    Commented Dec 30, 2022 at 2:55
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    \$\begingroup\$ @NickAlexeev Not by itself no, but it suggests context that may be relevant. The only thing I've driven with that much current is IGBT modules. Which have enough current flow, and stray inductance, that bootstrap drivers simply aren't usable. They need higher drive voltages too, in particular, negative Vge(off), which none of these types can do. \$\endgroup\$
    – Tim Williams
    Commented Dec 30, 2022 at 4:30

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The MOSFET driver you are using is mostly designed for low side gate drive, but with a separate boost charge pump, you will probably need to use a high speed optocoupler.

But you might be able to use a high side driver like LTC7001 and use its output to drive your TC4451.

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