cant find a decent SMPS for a current project.


2010-06-23 9:58 pm
Hi All,

I'm having difficulty finding a suitable SMPS for a current project.
I need a single or dual output with a voltage of 20v,0,-20v (+-2v either way would also be fine so 22v,0,-22v or 18v,0,-18v) and a power rating of 60-120w. Needs to be have as small form factor as possible, have a switching frequency of 100k (or higher). Ideally it would have PFC and accept world wide power input of around 90-270v AC.

For interest this is to power some tiny little surrounds/bookshelf speakers
that I want to actively crossover and Bi-amp using 2 little 30w class d amp modules that have the above requirements.

I have the amps now and am desperate to try them out, but am having know joy. Any help or nudges in the right direction would be much appreciated!

Kindest Regards

The ratings look similar to those of laptop adaptors with the exception that these aren't symmetrical, so take two.

Connect the plus from one adaptor to the minus of the other and use that as the common. The remaining two (minus from one, plus from the other) will then be your negative and positive supplies.

This is identical to what happens if you switch a dual laboratory power supply into symmetrical mode.
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