This is an old trick to save batteries from draining when you don’t have an on/off switch and don’t want to take out your batteries between usages.

Plus I take a few current measurements to show the current usage is ~200uA when not used for charging. This stand-by current is just to power the circuit when not being used.

An on/off switch would have prevented this ~200uA stand-by current but would have complicated the build and increased the product price. So slipping in a bit of paper between two batteries or an end connector does just the same as a switch. This trick brings the stand-by current to 0A and the batteries are good even a year later instead of being dead.

Yes, taking the batteries out works and is better but is more difficult and you have to find your batteries when you need to use your MintyBoost.

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