William Chops Westfield wrote:
>
> Of course, if you have a DC wall wart, then a bridge rectifier on the
> board is a convenient well of isolating you from the polarity of the
> connector...
>
> BillW
>

I just opened a new 12VDC 1A wart and got 15.6VDC with a 130mA load.

Minus 1.2V bridge = 14.4V.

That leaves 1.4 V which rules out a 78xx reg, but the LM2930-x will
work.

I am thinking, I will specify that regulator so I can use a DC wart and
then I only need smaller stabillity caps on the regs instead of the big
1000uF beasty.

I can also dispense with the bridge and use a single IN4001 to provide
battery reversal protection, and get an extra 0.6V.

That also leaves the wall wart open for other uses too if need be.

The savings on the cap and bridge can then help pay for the other reg.

--
Best regards

Tony

mICro's
http://www.picnpoke.com
mailto:sales@picnpoke.com

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