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LED Car Badge/Emblem/Shield Answered

Hi there,

Firstly, I am a mechanical engineering student with a limited knowledge of circuits and electronics, so therefore I may be a little out of my depth. However I am very keen to learn about electronic circuits and have completed other simpler projects and that is why I am attempting this project.

So onto my dilemma, I want to use my universities Shield of Arms to make a car badge for the single-seater racecar we are building as a project. However this badge won't just be a run-of-the-mill plastic car badge. I want it to be made from stainless steel (laser cut) and acrylic with the idea that I will solder a bunch of LEDs in series and when the ignition is turned on, the LEDs light up one at time until they are all lit, after which they all flash three times together and then remain lit up until the ignition is turned off.

The LEDs I intend on using are 0603 SMD LEDs and the aim of this whole design is that it is reasonably thin (No more than 1/4 " or 6.35mm thick for the PCB however ideally I would like it to be as thin as is physically possible. The dimensions of the badge will be very similar to a Porsche badge (51mm by 69mm). I have included the Shield of Arms in question and also the Porsche emblem for comparison. Also price is an issue since as I am a student, I have limited resources, so if someone could point me to some cheap electronics parts shops etc it would be greatly appreciated. (I live in the United Kingdom so a lot of American shops will be unavailable to me)

I don't really know how to read schematics but I do have friends working on this project who do,  however if anyone can guide me in the right direction with maybe a couple of how-to's (particularly the requirements for the lighting up process) and some really good pointers, it will be very much appreciated.

If I have not made myself clear I do apologise and I will be happy to explain further should you need to.

Thank you all in advance. I hope to hear from you soon.



After more research, and looking at the shields design, I have decided to scrap my original plan and use a NE555_SMD Timer to make all 23 LEDs (which I have now opted for 3258 SMD LEDs) flash for a certain length of time before staying on until the ignition is turned off. I was intending on using the schematic shown below, HOWEVER the schematic is for ONE LED and I want to replace it with 23 LEDs. Is there a way in which I can do this simply? i.e. Could I do a straight swap of an LED array made up of three LEDs in series in 8 parallel branches?

figure_01 (1).jpeg

you could use the 555 to turn on a small relay that could easily turn on your light array..just connect all of your leds in parallel with a single + and - terminal to connect to your circuit board...

That probably won't work, because of the much larger current you'll be drawing. The 555's max current is 200 mA and you'll be needing more (50mA per LED according to the specs). Besides that, I think the timing of the circuit will get "out of balance" by the higher current. Maybe it works with just four leds instead of 23... Just give it a try, see what happens.

Arduino is the way to go with applications like this...

for your chip....

someone at your school must have the dev board too. Just reflash the new chip.
Arduino is the easiest way to do this. You could also use 555 timers.

You need an arduino chip to run the sequencing ideally. Leds you can get from Rapid Electronics easily enough, but you'll need a bunch of 'em to be day light visible !

Thanks for replying. My Project Manager for the racecar is fond of Arduinos so I'll ask him about that. I already have a bunch of LEDs from when I changed the lights on my Xbox. Are you aware of any other small LEDs that emit a brighter light? To be honest though, I intend on designing it in such a way that it gives the maximum effect in low light conditions but still looks good in the day time, whether the lights are on or off. However in saying that, it would be a nice touch if it was at least semi-visible during the day.

You need lots of luminous flux out of your emitters. Small generally precludes high emissions.


Hi Steve,

Well I have done some research on high flux SMD LEDs and am considering my options as price will be a deciding factor, especially since we are know considering using a 3D printer for the shield.

I have one question about the Arduino chip though. Is it possible to use a Raspberry Pi instead of the Arduino? I only ask as I am reliably informed that we are looking to have a Raspberry Pi permanently on the car for data logging so it would make sense to use it for our badge.



A Pi would be huge overkill.Just use a single chip. The weight of the wiring alone would exceed using an Arduino chip.

I can see the weight being an issue.

Is there a specific kind of Arduino then that you would recommend? I have just taken a look at some of the Arduino products and some appear to be quite bulky, however I have no understanding of which one will be small enough and ideal for my specific application. Would you be able to point one out for me please?

I wouldn't use the whole board, I'd design a board with all my LEDs on it, and with just the chip needed. You MIGHT like to look at the LilyPad arduino board, or at least the chip there-on.

When you say 'chip' do you mean a certain IC on the arduino board that I'll have to remove?

I have never designed my own board before. What would you suggest as a board layout? I originally planned to have all the LEDs in series however I'm guessing some form of LED matrix is a more viable option for the way in which I want them to operate.

Also, I'm unsure how SMD LEDs actually work. I've tried researching them but to no avail. Do they need resistors in series with each one? And if so, which kind?

I apologise for being so clueless about this sort of stuff. I do try and research everything beforehand however my theoretical knowledge of these sort of things are a bit lacking.

SMD leds work just like ordinary leds, only they're a lot smaller.....Yes, they need current limiting