PI filtes ( was Re: switched mode power supplies
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Hi Jason, all,
I have used the PowerTrends PT5101 ($11.58-digikey-PT5101A-ND) with
only a large cap, 220uF, and no additional filters and the Simple
Switchers with cap and no additional filters. am I missing
something ? Should I be trying to eleminate higer freq stuff ?
I did make an effort to put the power stuff on one side of the board
and my ADC stuff seperated by a ground plane.
Dave
--- In basicstamps@y..., "jbirnsch" <jbirnsch@v...> wrote:
>
>
> National Semiconductor has a line of switching regulators called
> Simple Switchers. They have a variety of boost and buck converters
in
> fixed and adjustable voltages and up to 3A of output current. They
> offer software to easily configure a regulator based on your input
> voltage, output voltage, and output current. The only thing that
you
> have to be careful about is the layout of the supply. Use a ground
> plane if possible and keep feedback traces short and away from
> switching noise. Use a pi filter on the output to squash and high
> freq switching noise. It's all explained in the datasheets.
>
> If you looking for just a module to solder onto a board then there
> are a bunch of companies that make DC-DC converters. Power trends
(now
> TI) makes modules that will output 5V at 2A and are the size of a
> stamp. They cost about $10-15 each. You still have to add a pi
filter
> on the output because of the switching noise.
>
> Jason
>
> --- In basicstamps@y..., "Adrian Schneider" <adrian.schneider@t...>
> wrote:
> > someone recently mentionned switched mode PSUs - such as the
> > one used on the Javelin Stamp - and their advantages over
> > linear PSUs.
> > What about a "SMPSU-Stamp" - a stamp sized Switched Mode PSU of
the
> > kind of the Javelin's, may be slightly more powerful to drive some
> > external circuitry.
> > Wouldn't there be some interest in such a product if PARALLAX or
> > someone else would make one?
> > Regards
> > Adrian
I have used the PowerTrends PT5101 ($11.58-digikey-PT5101A-ND) with
only a large cap, 220uF, and no additional filters and the Simple
Switchers with cap and no additional filters. am I missing
something ? Should I be trying to eleminate higer freq stuff ?
I did make an effort to put the power stuff on one side of the board
and my ADC stuff seperated by a ground plane.
Dave
--- In basicstamps@y..., "jbirnsch" <jbirnsch@v...> wrote:
>
>
> National Semiconductor has a line of switching regulators called
> Simple Switchers. They have a variety of boost and buck converters
in
> fixed and adjustable voltages and up to 3A of output current. They
> offer software to easily configure a regulator based on your input
> voltage, output voltage, and output current. The only thing that
you
> have to be careful about is the layout of the supply. Use a ground
> plane if possible and keep feedback traces short and away from
> switching noise. Use a pi filter on the output to squash and high
> freq switching noise. It's all explained in the datasheets.
>
> If you looking for just a module to solder onto a board then there
> are a bunch of companies that make DC-DC converters. Power trends
(now
> TI) makes modules that will output 5V at 2A and are the size of a
> stamp. They cost about $10-15 each. You still have to add a pi
filter
> on the output because of the switching noise.
>
> Jason
>
> --- In basicstamps@y..., "Adrian Schneider" <adrian.schneider@t...>
> wrote:
> > someone recently mentionned switched mode PSUs - such as the
> > one used on the Javelin Stamp - and their advantages over
> > linear PSUs.
> > What about a "SMPSU-Stamp" - a stamp sized Switched Mode PSU of
the
> > kind of the Javelin's, may be slightly more powerful to drive some
> > external circuitry.
> > Wouldn't there be some interest in such a product if PARALLAX or
> > someone else would make one?
> > Regards
> > Adrian