Introduction: Usb Powered Blinking Led
i will show you how to make a led blink and use a usb port of the computer as a power source.
Step 1: Materials
What you will need:
1] 555 timer
2] 1k ohm resistor x2
3] 100 ohm resistor
4] led{any color i used a green}
5] capacitor [depending on the blinking rate. see next step}
6] circuit board
7] usb male connector
8] 555 timer holder {whatever it is called}
Step 2: The Capacitor
you can use any capacitor in the range of 10uf to 1000uf depending upon the blinking speed.
if you take a capacitor of less value will blink the led faster.
if you take a capacitor of more value will blink the led slower.
i used a 100 uf capacitor.
Step 3: Solder the Circuit
here is the circuit digram . solder the the circuit according to the digram.
Step 4: Connect the Usb Connector
we will need only the red and black wire.
my connector had red and a blue wire.
connect the red wire to the positive terminal of the blinking circuit.
connect the black wire to the negative terminal of the blinking circuit.
Step 5: All Done
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my e-mail id is rohit1398@gmail.com

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6 Comments
10 years ago on Introduction
Do you have to program the 555 Timer Chip?
11 years ago on Introduction
its called an electrolytic capacitor, not electrolyte
Reply 11 years ago on Introduction
wats kept in the spelling??/
Reply 11 years ago on Introduction
uhg first off you dont make sense and I see this is a totally lost cause.
Reply 11 years ago on Introduction
kkkkk
12 years ago on Introduction
To save a considerable amount of time and expense, you do realize there are LEDs with the flash circuit built in. The USB port can support 10 or so wired in parallel, and an interesting thing, is that they all flash at slightly different rates, which makes the seem to flash randomly.
There are more self flashing options these days as well, pretty much any color, alternate between two colors, RGB flash, RGB fade, and some amber that simulate a candle.
Only make mention, as there is much better chance of success, and save some money, in these tough times.