-----Original Message-----
From: pic microcontroller discussion list [mailto:PICLIST@MITVMA.MIT.EDU] On
Behalf Of Byron A Jeff
>
>Let's back it up, as your requirements are all over the place.
>
>What circuit do you have? How is it to be powered? What choices do you have
in terms of powering it?
>
>As the designer, I think you may be making a mistake allowing so many
different voltages to power the circuit. Spend a minute explaining why
someone should be able to plug in 3 different voltage power supplies into
this circuit.
>
>Often added complexity leads to failure.
>
>Hope to hear back soon.
>
>BAJ

Byron, you are actually right.  The only absolute requirement for this
circuit is that it should be run either from 3V or 5V.  I got carried away,
since this is a design for an industrial product, that it would be wonderful
to make it work at 24V, so I decided to have it run from 3V to 30V.  This, I
think now, is a bad idea.

What the circuit does (or should do): Converts pulses from hall sensor to a
reed realy and it needs to be able to run with both 3V and 5V.  That is it.

Currently I have a 3V hall, I try to convert the pulse output 5V and connect
it to a 5V reed relay.  If I use a 5V hall everything works beatifully with
5V but not 3V.  If I use stepdown dc/dc then the circuit only works with 3V,
not both.  I do not want to create 2 boards 1 runs with 3V and 1 runs with
5V.

I did not want to write the spec and let piclisters figure it out, that is
why I have been struggling and stuck and the ideas are all over the place.
I hope what I am eventually trying to accomplish is clear.

Thank you for you response,

Regards,

Omer

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.