>> First impression could be a quite twisted design for it's final
>> function, don't you think ?

It has it's mysterious aspects.

Why is there both a discreet implementation of a 5V linear
regulator AND a 7805-style 5V regulator ?  Startup issues?
Given USB specs, why can't the 10f controlling the switcher
operate directly from Vusb ?

Later on, there are all those multiple resistors in series.  IIRC,
Olin made some remark about that being done to limit the number of
different parts used on the board, but I bet it does a fine job of
confusing someone just beginning to do circuit analysis...

BillW
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