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Author Topic: Voltage Drop in Battery of standalone arduino  (Read 317 times)
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Hi guys,

I have set up a standalone arduino board with a LCD display and a FSR sensor. It is powered by a 9V battery and has a 5V voltage regulator.

I am finding that within 5 minutes of operation, the LCD begins to dim progressively.

Upon checking the voltage of the battery, it seems that it is at ~7.5V when the circuit is switched off. When switched on, the voltage drops constantly and the LCD is no longer visible when the battery reaches ~4.9V. And when switched off again, the voltage of the battery slowly rises to 7.5V again.

And another possibly helpful point is that when the LCD is dim and the reset button is pressed, the LCD becomes momentarily visible (or bright) again.

Any ideas, suggestions, or advice on how to fix this?

Left Coast, CA (USA)
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Any ideas, suggestions, or advice on how to fix this?

Certainly, just don't use those small 9vdc batteries to power any practical arduino project. The mAH energy capacity, maximum current flow capacity, and very high price per power delivered is just terrible for those. 9 vdc batteries are great for powering smoke alarms but not for arduino projects. If you require battery power for portability then research the various capacities and cost and select a rechargeable battery that can support your project.


the land of sun+snow
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Yes, tiny 9V batteries, forget them. Try a set of rechargeable NiMH AA-cells,
nowadays they have 2500 mAhr of energy store, probably 10X-15X as much as
your little 9V battery.

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