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How can be perfect (ideal) diode use in 80V step up instead normal diode?

I mean something like this circuit:

enter image description here

I'm searched it on the internet and I find just something like synchronous step up, is that the same thing?

And what will happen with MOSFET transistor if it'll be exposed to 80V reverse voltage? (why it can handle reverse voltage in ideal diode but it can't when inductance load is turned off?)

EDIT: By step up (or boost conventer) I mean this circuit: enter image description here

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  • \$\begingroup\$ why it can handle reverse voltage in ideal diode but it can't when inductance load is turned off? When an inductive load is switched off and there is no path for the back EMF current (no flyback diode) then the voltage will increase to a very high level. You should still not exceed a MOSFET's reverse voltage so the flyback diode is needed. \$\endgroup\$ – Bimpelrekkie May 6 at 6:44
  • \$\begingroup\$ +1 for changing "Is it possible.." to "How can...", now your question is much more clear. You saw a circuit concept and ask how that can be used in a different circuit. That makes it a good question. \$\endgroup\$ – Bimpelrekkie May 6 at 7:16
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The switching controller 'knows' when current should flow, so it is indeed possible to replace the diode with a MOSFET that is switched on at the correct time. This feature is called "synchronous rectification".

For example, this is how it is implemented in the TPS61322 (the inductor is connected to the SW pin):

TPS61322 function block diagram

However, most chips do not have integrated transistors capable of handling 80 V.

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