Wallwart

hmlittle59

Hello All,

How do you calculate the Max. "Amps" Wallwart to use? I've calculated twice the Max. circuit usage at any peek time or is there a specific Formula?

1) LCD Backlight on.
2) DS1302 operating
3) BS2e pin input/output
4) LEDs ON
5) Activating relay drive

ADD all these together (*) 2 = Max. Draw of Current. How do Ya'll calculate it?

Thanks

Howard

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I'M STILL LEARNING SO MUCH...BUT STILL KNOW SO LITTLE!!!

hmlittle59

mctrivia

the max amps for a wallwart should be greater then the maximum current draw your system could draw.

A safe bet is double the current draw of everything on. If that value starts getting really large then you may need to look into what actually can be on when, and possibly using caps to smooth out the current draw.

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Lots of propeller based products in stock at affordable prices.

hmlittle59

Thanks,

I did the latter part. I calculated the BS2 turn on rating and any other part when it is on(LEDs, DS1302, etc.) then I doubled it.

Thanks alot

Howard

Wallwarts COST to much!!! wow..I just did know the price range and the cost difference from Company to Company...

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I'M STILL LEARNING SO MUCH...BUT STILL KNOW SO LITTLE!!!

hmlittle59

al1970

Hi:

You have to be carefull; some wallwarts do not put out a DC that is good enough for chips. You need a switching wall adapter. If you need one that puts out less than 1 amp at 5 volts, let me know. I can sell you one for a few $ plus S/H. If you need many amps then a wall adapter just won't work.

Al