400*V DC/DC*Converter with a Choke
Since the transformer used currently in the converter block may be problematic in terms of availability and construction, I have decided to design a compatible converter using a choke.

The tube has to be powered with a voltage of ca. 400 V. Because the MC34063 has not been originally designed to work with such a high voltage, we have to use an external transistor working as a key. Such a use of the MC34063 is nothing new: a similar schematic diagram can be found in a STMicroelectronics datasheet.


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