I want to convert a constant 12V to a constant 5V .
would the schematic work?
d4 is BZV55B5V1 (datasheet)
the igbt is IXYP60N65A5 (datasheet)
Question for an electronics forum, sorry.
ok. thank you for the info. 
Why not use an off-the-shelf regulator IC? That way you get over-voltage protection, over-current protection, over-temperature protection, all included and dirt cheap. There is surely no case for trying to make your own.
i need quite high current .
Designing a high current power supply is not trivial. It does not combine well with the question of whether your proposed circuit would work (at all). I suggest you start with something smaller, do some simulations, also build some circuits on a breadboard or perfboard, compare the results and then extend on the things you’ve learned.
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Ah, so that’s the sort of thing worth mentioning in your opening post. How high is the current? Will it be sustained or in very short bursts?
There’s going to be some serious heat sinking issues to deal with if you are talking about tens of amps.
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less than 10A. i have also a big copper heatsink.
I have not used an IGBT but this schematic is just an emitter-follower and sure the output voltage is reasonably regulated at about zener voltage less 0.7V.
The problem is you are dropping 7V across the xstr and wasting a lot of power as heat you need to get rid of (eg: 14 watts waste heat at 2 amps out).
A switching buck regulator will get you an efficiency in the 80/90-ish percent range.
The problem is that I couldn’t find an ic that could handle enough current (10A).
Switching regulators are the default at high currents these days. Electrical efficiency matters when you are paying power bills and worrying about cooling
In addition to me generally agreeing with the other comments above, there are at least a few problems with the circuit.
- The gate-to-emitter voltage of the IGBT is not precisely known. Whereas a bipolar transistor will have (for example) 600 mV - 800 mV base-emitter, the range of IGBT gate to emitter voltage can vary much more than that 200 mV range. You might get 2V out or maybe 4V out. It will probably vary a lot with the temperature of the transistor.
EDIT: I just had a look at an IGBT datasheet. With my Avatar being an IGBT, I felt somewhat responsible!! 
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(12V-5V)=7V. With 10A of current you’ve got 70W of heat. That is a lot to dissipate without a fan and a large heatsink, or maybe some sort of water cooling. That makes no sense.
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IGBTs are intended for high voltage switching. I am not sure how well they will work as a dissipative pass element.
Closing this as nothing to do with KiCad
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