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Immune_Jam
04-26-2007, 05:10 PM
Hello Everybody,

This is my first post, and I am pretty new to most of this. I bought a PDB and a BS2px24, and have a question about power supply.

The recommended supply for the PDB is 12V@1A, the BS2px24 gets powered via the board and all is well!

My question is: I have lots of power supplies doing nothing, between 9V and 12V. However, none of them operate at 1A. What is the limit in current supply to the LM1084 for the board/BS2 combo.

I hope to be able to learn as I go and my son and I eventually want to build a robot, but it's baby steps for us at the moment.

Thanks for any suggestions.

Damian

RDL2004
04-26-2007, 06:50 PM
For the smaller experiments and projects you will be doing in the beginning, probably as little as 200 mA (or even less) will be enough. Just make sure the adapter you use puts out DC and not AC and that the plug is the right size with center (tip) positive.

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- Rick

Immune_Jam
04-26-2007, 06:53 PM
Thanks Rick, is there an upper limit that I should not exceed?

RDL2004
04-26-2007, 09:53 PM
There's not really a limit on the current, electronic circuits will only draw as much current as they need. The amp rating on power supplies is the limit on how much they can supply·when needed. For the voltage, you don't want to go too high because the excess is "burned off" by the regulator on the PDB, causing it to run hotter at higher voltages. Anything in the 9 to 12 volt range will be okay.

You should be aware that most of these adapters are not regulated and their voltage spec is for when they are fully loaded, so when little or no current is being used, the voltage tends to rise. A 9 volt un-regulated adapter will be closer to 14 volts with no load.

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- Rick