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 Message Boards » » bar graph LED for battery meter? Page [1]  
BigMan157
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If i were to connect each anode of the LED bar graph to a diode with like a 1V turn-on (10 anodes, 10 diodes) and then attach to those diodes resistors of increasing impedance, and then connect all those resistors to a power source, would that make it function the way I wanted?

I think it would but i might have to use some current limiting diodes or something

[Edited on November 7, 2005 at 7:30 PM. Reason : i'm trying to think of a way to not need an MCU for this]

11/7/2005 7:30:13 PM

benz240
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doesn't voltage stay the same even as the battery wears down? current drops, right?

11/7/2005 7:41:54 PM

Aficionado
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they both do

11/7/2005 7:46:17 PM

State409c
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Do a google search and this should yield what you are looking for. Are you actually wanting a power meter, a current meter, or a voltage meter, because accomplishing these is different.

11/8/2005 3:15:02 AM

State409c
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hello?

11/8/2005 3:28:15 PM

SandSanta
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High energy power meter. Extreme.

11/8/2005 4:53:45 PM

BigMan157
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i found a chip that will control it

11/8/2005 8:48:29 PM

Charybdisjim
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Quote :
"doesn't voltage stay the same even as the battery wears down? current drops, right?"


The internal resistance of the battery increases while the ability of the battery to supply power decreases. Ohm's law and blah blah blah, so yeah like he said, both go down.

11/8/2005 9:22:44 PM

Quinn
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LM3914N

[Edited on November 8, 2005 at 11:24 PM. Reason : .]

11/8/2005 11:20:34 PM

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