Hi Jon !

Jon Baker wrote:
>
> Does anyone know of a dc/dc convertor that will change 5 into 15v?  All the
> ones I found so far only go up to 12 and that's not good enough for
> programming with. The circuit has got to run of batteries so I suppose it
> could be 6v but it's got to be kept small.
>

If i got it right, you need a step-up converter to generate Vpp for
programming
a pic ( or an other EEPROM device).

For this purpose i am using a step up converter based on a TL497. It is
an old chip, but it was cheaper then modern switcher controllers from
Linear or National. I used a fixed unductor. Dont know if the current is
in the right limits, but it works.

There is a data sheet and an aplication note somwhere on the Texas
Instruments
web server.


If you want to build such an converter and don't find this documents,
i could try to dig up this files.

Hope, it helps.
St.