> Is there an optimum value for the decoupling, say 0.1 uF? or
> is it more the better?

Custom is some non-elco, .1uF ceramic or the like for the HF needs of
the uC itself. Add an elco when less HF variations are expected
(10..1000uF will do in most cases, maybe more - or better: other
measures - when relais, motors or LED displays are used).

Wouter van Ooijen

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Van Ooijen Technische Informatica: www.voti.nl
consultancy, development, PICmicro products

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