acbOct 11, 2023
This is thoughtful design: Muji apparently released a flashlight that works with any combination of 2 AA and 2 AAA batteries, only more dimly with fewer batteries.
Show thread-> @haileys.questOct 12, 2023
@acb I've always assumed that things that "require" X many batteries of X type are depending on all batteries to complete the circuit, not to mention the specific voltages of certain types of batteries. If that is true there's probably a way around it and that's probably what they did -- it's probably more components though and therefore more costly (although, to be fair, it's probably pennies on the dollar per hundred units or whatever).
Show threadCharlie Stross
@blake @acb I seem to recall reading some years ago that Microsoft had patented a *really simple* circuit to allow devices that run on one or more AA or AAA cells to auto-sense which way the batteries were inserted and flip polarity as necessary to operate. Can't imagine why this isn't in universal use already …
Oct 12, 2023 at 10:27amWeb
Show threadPete Prodoehl 🍕Oct 12, 2023
@cstross @blake @acb Probably cost.
Show thread@[email protected]Oct 12, 2023
@rasterweb @cstross @blake @acb Possibly also robustness - another component means another source of failure.
Show threadBornachOct 12, 2023

@rasterweb @cstross @blake @acb

Probably more costly than a full bridge rectifier that minimizes the diode voltage drop

Show threadJaime HerazoOct 12, 2023
@bornach
I can hear this image
@rasterweb @cstross @blake @acb
Show threadAMSOct 12, 2023
@cstross @blake @acb It costs another buck or so and fitting AA cells is heavier and thicker than a tiny prismatic Li cell these days.
Show threadLisPiOct 12, 2023
@AMS @cstross @blake @acb I like that their failure mode is typically less violently explosive though.
Show threadAMSOct 12, 2023
@lispi314 @cstross @blake @acb Yes, but sadly you're not the product manager who has terminal Apple brain.
Show threadLisPiOct 12, 2023
@cstross @blake @acb We have yet to #AbolishPatents so that might be it.
Show threadHenriOct 13, 2023

@cstross @blake @acb

This is not a new thing. I've seen wireless mice that can take one or two batteries. They are wired in parallel, modern electronics can just work with really low voltages.

Show threadCharlie StrossOct 13, 2023
@slyecho @blake @acb Yes, but that's not the same as "doesn't care what polarity you insert first: automatically detects and compensates for it".
Show threadHenriOct 13, 2023
@cstross sorry, missed that part. Technically it could be done with simple diodes, I think.
Show threadCharlie StrossOct 13, 2023
@slyecho Multiple batteries in random order: not sure simple diodes suffice.
Show threadChrist van WillegenOct 13, 2023
@cstross @slyecho found it! https://news.softpedia.com/news/Microsoft-InstaLoad-Makes-Polarity-Irrelevant-for-Battery-Installation-146039.shtml
Microsoft InstaLoad Makes Polarity Irrelevant for Battery Installation

The InstaLoad Battery Installation Technology is now available for licensing

softpedia
Show threadHenriOct 13, 2023

@cvwillegen @cstross this seems to be a purely mechanical solution instead of a rectifier circuit. Should be more efficient.

The order of the batteries wouldn’t matter because they are not connected to each other, only to the circuit after the polarity is corrected.