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Need Your Help on Placing LEDs on Laptop AC Adapter Idea

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New Member
Hello All,

First let me introduce myself as a total-electronics-ignoramus; second as the inventor of an enhanced laptop computer AC adapter power cable.

We are in the developmental stages of refining the design prior to actual manufacturing. Due to marketing agendas and such I can not offer detail as to the special function of this cable; however it's the aesthetics, the oh-my goodness-what-a-cool-looking-product that humbly brings me here before you with my need for your expert knowledge and willingness to help the dumb guy. So here goes:

Laptop computers have various AC power adapter configurations with DC output power generally between 60 to 90 watts, 15V to 19.5V, 3 to 6 amps. These are the numbers you'll see on the transformer thingy. It looks to me like you could damn near start your car with these things. The burning question is: is it possible -- without too much expensive circuitry -- to place lets say six 3mm LEDs around the connector which plugs into the computer. (Macbooks and some new PC laptops have LED ring lights there)

Is there a simple way to implement this? Are there resisters that can deal with such a large discrepancy of power...as I know LEDs are miliamp creatures? Can we get by with a single resister? Or what? I'm clueless.:confused:

Any and all help, guidance and opinions will be welcome and greatly appreciated.

Thank you!


Couldn't even come close to starting a car, the amp draw of a car starter is in the hundreds of amps. So 1000+ watt minimum.

You would want some kind of control circuitry coming from the power supply for the LED's it's the only really practical way of doing it, circuitry inside the supply would be able to tell when power was being drawn and switch on the LED's, but you'd need to run extra wires in the power cable for the LED's. Seems like a lot of effort for a little bit of silly eye candy. Though knowing the PC market there is a small portion of people that will pay insane amounts of money for eye candy like that.

If you don't know what you're doing then spec the project out to a company that does know what it's doing.
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Well-Known Member
Hi JT,

Don't wish to pour cold water on your idea - but suggest you research further into your idea first - have you checked if a similar idea is already patented - many good ideas are patented just to stop them being produced - I think such a laptop power lead will be one of them.

Also look very seriously at product liability if you are manufacturing and marketing a mains AC device - try and find what the cost of insurance for such a product would be - there's always someone going to stick there fingers in the wrong end !
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