# Self MadeSequential Led Turnsignal ??



## Ducati 1098 (Mar 24, 2011)

I am customizing a motorcycle with 11 5050smd led strips.They will be hooked up to the brake light. I would like each strip to turn on .5 seconds apart or so... How do I go about this??


----------



## Changchung (Mar 25, 2011)

Hi, try with this circuit:

http://www.allaboutcircuits.com/vol_6/chpt_7/6.html

You have to use a 5 volts regulator for use in 12 volts if not you can blow the CI, them you need to put in each output in the 4017 a transisitor to 12 volts, that way you can run the strips Leds...


----------



## rwolff (Apr 20, 2011)

Ducati 1098 said:


> I am customizing a motorcycle with 11 5050smd led strips.They will be hooked up to the brake light. I would like each strip to turn on .5 seconds apart or so... How do I go about this??



One option would be to "kitbash" a truck part - there are commercially-available 6"x2" oval amber signal lamps with sequential arrows - find one with as many elements as possible, open it up, and run the LED strips from the driver circuit in the lamp. These parts are designed for an automotive environment, so you don't need to add a regulator.


----------



## DrScott (Jul 18, 2011)

I know this is an older thread, perhaps the OP has not made his project yet. Or it may be helpful for others.

0.5 second is FOREVER. It needs to be much faster--at 60mph 1 second is about 80feet--you *do* want to be seen as soon as the brake is applied. Don't ask me how I know.

To sequence it you need to either (1)use a microcontroller to sequentially turn on a series of electrical switches, for example, SCRs. (2) use a timer/decade counter to sequentially turn on the same electrical switches. Using an SCR is easy and cheap. once turned on it will stay on until the power to the load (here a string of LEDs) is removed. Thus, as they are turned on they stay on until the brake is released--the brake light 'grows' in intensity. It is important to use properly rated voltage regulators and protect them with diodes. Automotive applications are very 'dirty' with transient spikes and even occasional polarity reversals. Good voltage regulators are a must. 

Properly protected it is not too hard to do. You just need to provide a cleaner electrical world for the electronics.


----------



## DrScott (Jul 18, 2011)

I should add, not to get an additional post either, that ADDING a sequential brake or turn signal to the bike may improve your visibility to other vehicles. All LEOs I have spoken with understand the importance of making your bike more visible and will let a lot of stuff go. I, for one, would never remove/modify the stock lamps on a road vehicle. Legalities/ticketing aside, the liability of having a wreck that was really not your fault but, because you changed the lamps, even if they were "better," becomes your fault, is not worth it.

$0.02


----------



## dsrp (Jul 27, 2012)

Was reading this post and it reminded me of my sequential turn signals I made before.

I used a LM3914 bar graph IC chip. It will operate 10 led's or they can be daisy chined to do more if needed. It took some time to get things working properly but it was pretty easy. Use proto board to test things out then have boards made on one of the online board making sites.

Do a search on the LM 3914 chip and you will find many circuit designs using it.


----------

