GMorbe wrote:
>
> Hello Roman, All
>
> I think i go the discrete approach because of components availability
> reasons.
> The use of a capacitor for the hold time is clever but i dont like it,
> because the PIC would die down slowly by discharge unless you take special
> action to avoid this.
> Meanwhile i found a solution around the diodes to decouple the button
> information from their switch on function. By connecting the buttons to
> the - potential its possible to decouple them with resistors only. The
> values of them needs to be well defined however. See my picture.
>
> Germain Morbe

Hi Germain. I'm not sure I like the design. Your 12v
battery voltage is permanently connected to the two
PIC pins, which:
1. is way out of voltage spec!!
2. will drain battery into the PIC protection diodes.

Why not replace the 10M with 1N4148 glass diodes, these
are cheaper and smaller than resistors, and will
solve the two problems...
-Roman

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