Re: Home Brew Chargers anyone?

On Oct 6, 7:03=EF=BF=BDpm, "RogerN" <re...@[EMAIL PROTECTED]
> wrote:
> Years ago I started working on what was supposed to be an alternative to
=
the
> Alpha 4. =EF=BF=BDThe basic concept seemed simple enough but I wasn't
sur=
e how to
> get components to handle reverse polarity and short circuits without
smok=
e.
> About the time other multi-chemistry chargers came on the market, I quit
> working on it. =EF=BF=BDThe interest has been there and over the years
I'=
ve learned
> what I needed to know then. =EF=BF=BDAlso, now there is more available
in=
 free
> simulation tools, etc.
>
> I've been studying different switch mode power supply topologies.
=EF=BF=
=BDSEPIC
> would allow you to charge batteries over a wide voltage range but I
haven=
't
> found very high powered SEPIC controllers. =EF=BF=BDI have found Linear
T=
echnologies
> has Boost controllers that can give 50V at 5A (250 Watts) from a 12V
> (Actually 10V to 28V) source. =EF=BF=BDThen you can use a buck converter
=
to lower
> the voltage to what you are charging. =EF=BF=BDAdd some analog outputs
an=
d op-amps
> to allow a microcontroller to set the current and analog inputs to read
t=
he
> voltage and current and that should be a pretty powerful charger.
>
> I'm interested in getting something going on this and let the schematics
=
and
> firmware be open source. =EF=BF=BDThat way the software can be improved,
=
features
> added, or new charging algorithms added as new battery technology comes
o=
ut.
> If anyone's interested I can give links to the simulation software and
> circuits.
>
> I'm not sure on the microprocessor or microcontroller to go with.
=EF=BF=
=BDI want
> something that anyone interested can program for low cost.
=EF=BF=BDAnywa=
y, I've got
> to get the details ironed out and tested in the analog circuitry first.
>
> RogerN

Take a look at this one http://www.hughesrc.com/
It appears to be a
super Alpha 4.