how does the gamboy advance detect its battery life

[themist912]

How does it do it eternally I know theres the light but how does the circut actually work on it for it to function that way.

 

[Prog]

As batteries drain, the voltage gets weaker. The difference is small (like +/- 2V) but detectable.

For reference, here are two circuits that you can build yourself to detect a low battery.

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