State of Charge Indicator
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chainfire95
- Posts: 423
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- Location: Minnesota
State of Charge Indicator
Does anyone know how to create a SOC indicator circuit with more than 2 LEDs? I've been looking and haven't been able to find any info. I want to make one similar to this :
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chainfire95
- Posts: 423
- Joined: Thu Jul 30, 2009 11:13 am
- Location: Minnesota
Re: State of Charge Indicator
Bump
A truly wise man can entertain a thought without accepting it. A fool cannot withhold past judgments but instead closes his mine to new possibilities. Someone who wants to innovate simply needs to forget what everyone says isn't possible.
Re: State of Charge Indicator
If you take a direct voltage reading it isn't that hard. Basically you make a voltmeter with a 5 led bar-display.
Of course, If you are using rechargeable batteries, this will usually give you a display that sits right in the middle for 80% of the discharge cycle. Not very useful. (like how your digital camera might always say "low battery" when you put ni-mh cells in it)
So basically you have to measure the current going in/out of the batteries, count how much goes in, then count how much comes back out while updating some kind of display. Texas Instruments sells lots of chips that do this, but you are going to end up making your own circuit board, possibly all surface mount.
(maybe we should look into getting some kind of sponsorship from TI eh? what with us pitching them so often)
Of course, If you are using rechargeable batteries, this will usually give you a display that sits right in the middle for 80% of the discharge cycle. Not very useful. (like how your digital camera might always say "low battery" when you put ni-mh cells in it)
So basically you have to measure the current going in/out of the batteries, count how much goes in, then count how much comes back out while updating some kind of display. Texas Instruments sells lots of chips that do this, but you are going to end up making your own circuit board, possibly all surface mount.
(maybe we should look into getting some kind of sponsorship from TI eh? what with us pitching them so often)
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thewise1
- Portablizer Extraordinaire
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Re: State of Charge Indicator
You can use mario's guide for a low led light. To make multiple ones you just add a second circuit except with a higher voltage diode. And if you want it so it's not always on, just add a push button tact switch to the main power source.
http://forums.benheck.com/viewtopic.php?f=20&t=27829
http://forums.benheck.com/viewtopic.php?f=20&t=27829
