Comment on bypass controller on a cheap LED strip

• VehicleTree@lemmy.ca ⁨2⁩ ⁨days⁩ ago

  Are you checking between the 12V and one of these legs? It’s typically connected to ground in these types of controllers. Here’s the SOT23 pinoutfor reference if that is the same package.

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• CameronDev@programming.dev ⁨2⁩ ⁨days⁩ ago

  You can’t check for ground specifically, you just check for a 12v difference between two points, and call those +12 and GND.

  Feels odd that they are pulsing the entire 12v line, but I’m guessing it was something cheap.

  The bottom leg of the transistor definitely looks like GND to me, so I think you just want to probe around (carefully!!) to find the stable 12V. I would avoid the entire live side, and for safety, might be worth taping it up.

  If you cant find a stable 12v, you may want to get a cheap 12v power supply? Old laptops are often 12v, power too chargers as well are often 12v.

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  • dingdongitsabear@lemmy.ml ⁨2⁩ ⁨days⁩ ago

    measuring difference between ground plane and the various points didn’t give me a stable voltage. the black thingy leading to the 12 V line is a SS210 (search says that’s a schottky diode) and on its output the mentioned fluctuation is happening. on its input there’s some very low voltage happening, like sub 1V (got a shitty multimeter).

    if I’m understanding this correctly, then this thing boosts the voltage but the fluctuation is happening somewhere else. in other words, there is no 12 V source on this board. or?

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    • CameronDev@programming.dev ⁨2⁩ ⁨days⁩ ago

      Maybe you can trace that low voltage fluctuating line back to one of the ICs?, and work put how to disable that IC?

      Or, use the remote to output solid white, and find the voltage on that line, and then try find that voltage somewhere else and short the two?

      I’m running out of ideas though, I suspect buying a cheapo power supply might be easier :/

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      • dingdongitsabear@lemmy.ml ⁨2⁩ ⁨days⁩ ago

        that’s a solid line, I’m gonna try that. hopefully won’t burn nothing of value. thanks

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