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  1. dave9

    12 v to 48 volt dc boost converter 300 watt

    Yes it is technically possible, but not very practical. I hate depending on Chinese product specs (which are sometimes wrong) but this might work: https://www.ebay.com/itm/uxcell-Voltage-Converter-Regulator-DC-DC-DC12V-to-DC48V-10A-480W-Car-Truck-Boost/333124189559 Due to the wattage this...
  2. dave9

    Reducing voltage for a driver driven LED strip

    Yes, a series resistor is one way you can do it. Measure the current when it is running at the desired brightness, in this case at 3.3V if you've settled on that, then plug the numbers into an LED calculator. You should also decide whether you want that target brightness at the vehicle...
  3. dave9

    LED Display (Home project)

    I'm talking about your pathetic effort to merely post some little 350x350 res. image as if we're then supposed to use that to engineer a product for you and then give you a parts list. I did not link for just the picture, rather the PRODUCT and some specs. Again, you are not motivated enough...
  4. dave9

    LED Display (Home project)

    You are not motivated enough to build this from scratch. My interest is very low and yet I can at least manage to post a link to the product: https://www.alibaba.com/product-detail/led-panel-for-football-field_500223002.html If you want to learn about it, buy one and reverse engineer it.
  5. dave9

    LED Display (Home project)

    You are starting with too little and asking too much from help in a forum topic. You did not state your skill level but I suspect the learning curve will be too steep and that you are better off getting more of a generalized electronics education before tackling such a project, then once you...
  6. dave9

    LED Light Fading Problem

    You might need to replace both to get them to match best, and personally I would still measure the current and consider if they might benefit from a little less current by swapping a series resistor.
  7. dave9

    LED Light Fading Problem

    My first suspicion would be that this is a dodgy design where they drove the LED with too much current and/or used a generic supplier who overspec'd the allowable current. Why do you suspect the capacitor? You could get the chip datasheet and see what the function is of the pin it's connected...
  8. dave9

    Protection of Lithium Batteries

    You do not need to do anything, as long as you use two *identical* batteries, otherwise if they have different voltage levels one may drain the other or at least they won't share the load equally, neither of which is necessarily a huge problem, rather it just means replace the batteries both at...
  9. dave9

    consolidating individual LED interior-lighting drivers?

    The other option is pick different LED modules that can operate from under 30V (though you never did tell us your location and what the code limit on voltage is there?) and then search for a dimmable low voltage system driver, at each LED fixture. I don't see a way to get around a per fixture...
  10. dave9

    consolidating individual LED interior-lighting drivers?

    A typical LED driver has a current sensing feedback. Its output goes through a low ohm sense resistor, and measures the voltage drop across that and compares to its internal reference voltage. It varies the voltage to achieve a specific current, thus current regulated. It lets the voltage...
  11. dave9

    consolidating individual LED interior-lighting drivers?

    The voltage range of the driver is more about allowable range, and yes it would need the sum of (n # lights) x 280mA capacity but that plus some margin for good lifespan is only the full brightness state. You want the opposite, a variable-current, though current regulated dimming driver. I...
  12. dave9

    Display TV input!?

    You seem to be telling us something weird instead of the make and model of TV. It's not a display TV you're listing, it's the panel in it, which has LVDS connections. You'd connect a PC to the TV mainboard inputs, not directly to the panel. For example "I have a Seiki LC-55TD5 TV which just...
  13. dave9

    EDLC and Li-ion hybrid supercapacitors - claims that don't add up.

    I just tried it on Chrome Version 76.0.3809.132 (Official Build) (64-bit) and supsup works, is always visible. Chrome updated itself while I was doing that, is now Version 77.0.3865.75 (Official Build) (64-bit) with no supsup change. You might try running Chrome in safe mode to see if you have...
  14. dave9

    EDLC and Li-ion hybrid supercapacitors - claims that don't add up.

    It has nothing to do with Win7, which I am currently using and see it on Firefox. It's all the browser.
  15. dave9

    Where could I salvage an LM317 Voltage regulator?

    Everyday appliances, none that I can think of. You'd be far more likely to find an LM7805 in something with some semblance of logic control rather than manual switches and mechanical timers. You seem to be going in the wrong direction with your project. Your laser driver is for 2.5W or higher...
  16. dave9

    Auto radio keeps restarting when theres no key on ignition

    Direct on a car battery is not the same thing. As Martaine already mentioned, you have one wire that should be constant live 12V for memory and clock function, and one wire switched off with the ignition of the vehicle. It seems fairly clear that your vehicle is not switching the main power...
  17. dave9

    Light bulbs as dummy load for Stereo ?

    Won't a 12V bulb be too near the amp output voltage to keep the resistance anywhere near constant?
  18. dave9

    Light bulbs as dummy load for Stereo ?

    Series parallel array of incandescent bulbs in a freezer with a thermal detection liquid nitrogen spray for the win!
  19. dave9

    consolidating individual LED interior-lighting drivers?

    I think the largest problem you're going to have is finding something dimmable that runs over a low voltage supply, unless it's some fancy smantzy smartphone controlled module or something, and I have no specific knowledge about those. If you must have them dimmable, and can't find a low...
  20. dave9

    Light bulbs as dummy load for Stereo ?

    You mean something you built yourself, or repaired, and question its proper function? I usually just measure to be sure there's no DC on the output (if applicable), then first hook the amp up to crappy low value speakers, actually just a loose driver I got out of something or other a long time ago.
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