You should know by now, counting is not one of my strengths 
But thank you very much for your help! It often takes me a little longer to understand things and I can only go further once I have recognized my mistakes.
You are absolutely right, the first circuit is very uncertain. I could use the 3.3V instead of the battery at the source of the p channel, but then I am afraid of noise and will probably also reach the limits of my LDO.
That's why I'm currently tend to the second circuit. I hope it will work this way.
Is there anything else to criticize about the BSS138, or a suggestion for a better alternative?
