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Usb lamp with...(help)

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Hihobear

New Member
Hello, could anyone tell me what and how I achieve this:
I have a usb LED, it's built with a cut off usb cable, a 180ohm resistor and the LED. Anyway, since I don't want it to be on all the time I want to add an additional function. When the lamp isn't shining, you flip a switch or a button and the LED starts to shine for a certain amount of time (let's say one minute for example).

Sooo, how would I achieve this?


Thanks!
 

MikeMl

Well-Known Member
Most Helpful Member
Google NE555
 

MikeMl

Well-Known Member
Most Helpful Member
Last edited:

Hihobear

New Member
Hey I'm back with some basic questions! :D
Well first of all, let's take a look at the picture you linked. The 555 is only that box right? All other things are on the outside? Because if that's the case, how would this look in physical form? Would it take up a lot of space?

Secondly, it says "predetermined amount of time ", how long exactly is that?


And lastly, the "relay coil" is supposed to be replaced by the LED and its 180ohm resistor? Is that what you mean with "Replace the relay in the referenced circuit by your LED and its current limiting resistor. "? Or am I supposed to place the resistor elsewhere (like replacing the 100k resistor or something like that)?


Thanks!
 
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