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Delay before each led lights ? Answered

I'm using: 12V supply, 3mm or maybe 5mm blue leds 3.1v (20mA) (288 pcs) 470ohm(?) resistors(288pcs) I want one led to light and stay lit, then I need a 6 hundredths of a second delay before 2nd led lights and stays lit then delay and  third light, and so on, and so on. All lights to remain on  as it goes... and until completed... then all off in order to begin a new cycle. (Approximate cycle time is 20 sec to light all 288 leds) Trying to create the illusion of handwriting with leds.What capacitors and other resistors do I need to cause the delays?  Wiring diagram plz. I'm a newbie. What size Fuse and its location? Thanks for not slapping me around to much. And thanks for helping.


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3 years ago

Hey! What I understand is that you want an array of 288 LEDs to light up one-by-one and stay on, like a progress bar (I dont get the "handwriting" part).

Fuses are always used in series with the supply and the value depends on the current that is being drawn by the system.

http://led.linear1.org/1led.wiz (for single LED)

http://led.linear1.org/led.wiz (for multiple LEDs)

Use these website to find resistance you should be using to avoid your LED getting 'burned'. However this website would'nt generate circuit according to your delay requirement and as far as I know you can make LED 'blink' with simple capacitor-resistor arrangement, not really sure if you could make them stay on and I doubt that you'll be able achieve your circuit requirements without the use of ICs and/or microcontroller

I would highly recommend you to use a simulation software (like Proteus or Multisim) before buying all these stuff and as a beginner you should not focus so much on a specific application (unless you're doing it as a school project), start off with a few LEDs, make small "LED progress bars" and make them work one after the other (hope it makes sense).