-----Original Message-----
From: NCS Products <ncs@WORLDNET.ATT.NET>
To: PICLIST@MITVMA.MIT.EDU <PICLIST@MITVMA.MIT.EDU>
Date: Thursday, May 28, 1998 8:10 PM
Subject: [OT] Doubling 12 volts...maybe use a 8-pin PIC!


>I need to double a 12VDC input to get 24VDC at .5 - 1A.
>
>This can be done, I'm sure, but how?
>I think the basic concept is, you charge two capacitors in parallel,
>then discharge in series.
>
>What type of switches (MOSFETS?) do I need, and how many.
>Any pointers to analog info would be much appreciated.


This COULD work, but the heat dissipation in the switches would
be horrific.  What you want is a boost converter, VERY simple.

Look up a datasheet on the CS384X series from Cherry Semi.
(also made by Unitrode and others)

A chip, A fet, an inductor, a diode, a big cap, and a few small Rs and Cs.

I've done 60W designs solely with Digi-Key parts, no custom inductors.