Hardware Misc DS LIte power light flickering between green and red

[elezzar]

I noticed on my DS lite that the before the power light goes a solid red it will start to flicker between green and red with button presses affecting this and causing it to turn red for a split second sometimes

After doing this for awhile it goes to solid red and does not flicker anymore

Is this normal? I presume its just because the battery voltage is nearing the voltage the low power sensor detects and little things that draw more current cause the battery voltage to drop below enough to cause the light to go red and then when less current is being drawn the voltage goes back up and the light goes to green...

But this is just my humble guess.
If anyone knows anything about this, and if its normal, if its a battery issue or some other malfunction, or if its just a hardware quirk? I'd love to know more

 

[Ryccardo]

Yes, it's purely voltage based (and no DS has a mechanical power switch like the GBAs to get dirty), unless there's some weird contamination on the board/battery pins it's just the way it is with a worn battery

 

[Nikokaro]

If anyone knows anything about this, and if its normal, if its a battery issue or some other malfunction, or if its just a hardware quirk? I'd love to know more

Nah, don't worry, it's a normal thing. When the battery is getting low for a few seconds it oscillates between green and red, and then stays red. Moreover, if you use a simpler, less demanding game it may turn green again for a few seconds, then settle on perpetual red, at least until the next recharge.

 

[elezzar]

Nah, don't worry, it's a normal thing. When the battery is getting low for a few seconds it oscillates between green and red, and then stays red. Moreover, if you use a simpler, less demanding game it may turn green again for a few seconds, then settle on perpetual red, at least until the next recharge.

Alright, thank you. that's good to know, I was worried something was wrong

Post automatically merged: Jul 15, 2023

Yes, it's purely voltage based (and no DS has a mechanical power switch like the GBAs to get dirty), unless there's some weird contamination on the board/battery pins it's just the way it is with a worn battery

Yeah, I don't think my battery is too worn but I'll try a new one sometime and see if it still happens as much, I have a feeling it will happen regardless. but its Interesting they don't have a counter measure keep it from fluctuating so much. just a chip that says after it goes red once it highers the threshold by a bit until voltage spikes again? Maybe that would be too expensive to manufacture for no reason other than aesthetic... But thanks for your input

 

[FAST6191]

More optimised code might put it in a low power state until something is pressed, at which point it then has to wake up, spin up the processor and respond to your input so that seems within the realm of reason which increases current draw and also voltage drop.

If it bothers you then you might be able to do a mod. Latching is the term you want to know in this, not so commonly employed or considered in day to day electronics these days or indeed even seemingly in the tuition thereof but is never the less a thing you can order up components for
https://kitronik.co.uk/blogs/resources/how-to-use-a-thyristor-as-a-latch
I don't know if it pulses them upon power on, or whether sticking the charge cable in might cause some fun but hey.
Alternatively a capacitor and possibly inductor circuit to act as smoothing might also do something for you.

 

[elezzar]

that's quite interesting actually.
I might look into possibly modding it someday but I wanna figure out how to also mod it have a better battery life calibration possibly three or four colors rather than just the two.

Doesn't really bother me much at this moment though

someday I'll build the perfect DS with USB C and a custom shell, retroglow buttons, etcetera and I'll include something like that

But thank you for the information!

 

[FAST6191]

Battery charge levels is largely a work of consumer placation (the percentage bar on phones and such being basically a work of fiction, even before the "I see you have charged this battery 1000 times so flip the wallet too fat error"), and you could also get all philosophical and spin this as at least a third colour/state -- not largely full power but also not too far into the drop. It can also vary between games (and sections within them -- I did some power draw tests a while back for some GBA flash carts and sitting at the menu in game vs in game for a GBA game was more than the difference between some flash carts), flash carts, probably brightness levels (which you can set by cheats), volume, using wifi and whether you have anything in the GBA slot.

 

[elezzar]

Battery charge levels is largely a work of consumer placation (the percentage bar on phones and such being basically a work of fiction, even before the "I see you have charged this battery 1000 times so flip the wallet too fat error"), and you could also get all philosophical and spin this as at least a third colour/state -- not largely full power but also not too far into the drop. It can also vary between games (and sections within them -- I did some power draw tests a while back for some GBA flash carts and sitting at the menu in game vs in game for a GBA game was more than the difference between some flash carts), flash carts, probably brightness levels (which you can set by cheats), volume, using wifi and whether you have anything in the GBA slot.

Honestly at this point I vote nuclear auxiliary power to the people.... but yeah I guess there isn't any constant voltage drop between games and settings and such

Maybe there's a better way to tell the power left in a battery? I mean I know we can't weight it and say "this one feels a trillion electrons heavier" but maybe it would be possible to knock electrons off of it and measure their density across an area or something like that.

Idk, shower thougts

 

[FAST6191]

You joke but alkaline cells bounce differently, though that is not this.

Also the electrons are probably the same (or near as makes no difference/thrown off by a mote of dust landing on it) -- charge flows after all and the current entering a junction is the same leaving it, it is more that the electrons have less potential energy (though textbooks will probably put it in terms of internal resistance of the cell).

There is also a reason any good data sheet will give voltages at charge levels for different loads (first result for lithium ion battery datasheet, page 8 https://www.ineltro.ch/media/downloads/SAAItem/45/45958/36e3e7f3-2049-4adb-a2a7-79c654d92915.pdf ). You could switch in a dummy load and measure voltage drops calibrated against things, or indeed get a sense of the internal resistance.

Much of this could also be obviated for most people by getting one of those nice portable power banks and a suitable charger (assuming you don't do a USB mod).