>  So, again my ideea is good then ! You need a circuit just for power-up
>the driver at the begining of the regulation process. A small oscillator
>to keep the driver supply until the feedback regulation voltage may
>supply continuously the driver.

Yes, that is one approach I'm looking at BUT it is unfortunately not quite
that easy in this application.
While there IS nominally a battery present with a 9v rating (dropping to
more like 5 volts in some cases) the presence of a battery may not be relied
on.
The alternative source is the wide ranging 0 to 130 volt supply.
If I voltage double off this supply I will get operation at about 5 or 6
volts which is acceptable BUT I will then need to disable the voltage
multiplier as I do NOT want it to multiply the 100+ volts to 200+ :-)

An alternative is ICs like the UCC3802 family (upgradeds alternatives to the
3842) some of which have 5 volt operation. Unfortunately they are several
times the price of the industry very-standard UC3842 series and much less
available.

>  I don't understand how you manage one decade input voltage variation
>(10...100V) but this is your business...


Alternator powered by a person exercising :-).
User speed varies and load varies which alters the terninal voltage seen by
the equipment.
Voltage is typically 10 to 50 volts at light loads and 5 to 15 at very heavy
loads but can rise to 130 volts with VERY enthusiastic user at zero load.
Worst case user MUST be designed for :-)
Under heavy loads 10 volts plus is not reached until an unacceptably high
user speed.


RM

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