buck converter
buck converter
(OP)
Hi, I'm in the design process of a non-isolated buck converter to get 70Vdc from the 115vac line and I have some trouble controlling my mosfet. I'm trying to control the mosfet from a microcontroller using a hcpl-3180 from avago technologie. The mosfet is on the high side, so I need a floating supply. Anyone can suggest a schematic how to connect it or suggest me another way of doing it thanks






RE: buck converter
Gunnar Englund
www.gke.org
RE: buck converter
RE: buck converter
Gunnar Englund
www.gke.org
RE: buck converter
Look up International Rectifier high voltage gate drivers for a better understanding of what I'm trying to describe.
RE: buck converter
Gunnar Englund
www.gke.org
RE: buck converter
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I don't suffer from insanity. I enjoy it...
RE: buck converter
Yes Lionel. That's a boot-strap circuit.
Wow scogsgura, I'm sorry I actually took the time to explain how the circuit works instead of leaving it up to Axher to find the right bootstrap circuit example. There's only dozens of applications for a "bootstrap" circuit.
Axher - to answer your last question. You would not need the bootstrap circuit if your isolated supply is available before the converter begins to operate. Otherwise, you would need it. But, the circuit can operate off of the bootstrap circuit alone so the isolated supply is somewhat overkill.
IR pushes this particular circuit configuration with their driver IC's but it could be done just as easily with that HCPL-3180 part. The IR parts have a number of app notes and voltage limits that you have to pay attention to or you can run into trouble applying their driver IC's.
RE: buck converter
so if I understand correctly if I want to use the HCPL-3180 ( http://ww
RE: buck converter
What is the extra optocoupler isolating?
I'm just suggesting you look at the IR parts to see what they're doing if you don't understand how to get your floating power supply.