We are developing DC/DC CONVERTER 5 to 1kV circuit. The picture is part of the DC/DC CONVERTER circuit we purchased and used. We created the same Voltage Multiplier and succeeded in creating 120Vdc with 10Vpp and 100kHz inputs.

Now I want to know what BJT (BF820W) and OPAMP (ADA4805-1) work in the picture I'm not sure about this structure. If you know anything, please give me any advice. Thank you.

 

XC6114 is a regulator. You can just think of it as a DC supplier.

 

The diagram of Part 2 appears to be missing its positive supply, which I assume is the junction of the three capacitors and the transformer where it says "BR102". Is that correct?